Here is the letter I send to my Infantrymen every campaign around mid August:
To the Infantry,
I value and respect all soldier classes. You guys have really helped, and I am forever grateful. And so it is with much regret that I write this letter to inform you of some unpleasant but necessary changes that need to be made to our squads. You see, recently Dr. Shen has been able to use alien technology to endow soldiers with incredible augmentations, that are not at all disturbing or ethically questionable. Augmented soldiers are now the best we have, and I must put the best soldiers on the battlefield. That means benching bio-soldiers to make room for these shiny new killer cyborgs. And coincidentally, these new heavy hitters perform much the same role as the Infantry, but do it better.
You have done everything we have asked, and this is not your fault. Your class was assigned randomly, after all. Just know that there will always be a place for the Infantry in our hearts, and also on Exalt missions.
Yours always, Commander
ps. For those of you who wish to remain in the line up, no matter the cost, there will be a meeting tomorrow, at 0700, in the cybernetics lab.
Infantry are not bad soldiers. They are solid shooters that offer little else; whereas MECs are incredible shooters, that offer little else. So what to do with the benched infantry? They add the most value as either back up officers, or by chopping them into Valkyries.
Executioner
Opportunist
Ranger
Sharpshooter
Sentinel
Vital Point Targeting
Executioner
In April and May this ability absolutely rocks. You will often be able to nuke a pod of thin men, or a flock of floaters, leaving at least one enemy with low hit points. With 2 shots and bonus aim, Infantry are usually able to polish off these targets, and allow your Gunner to suppress/holo-target other threats. Later in the campaign, Executioner retains most of its value, even if you don’t use the crit build.
Alternatives: Steadfast or Covering Fire
Steadfast is a great ability and a valid alternative for Infantry if you intend to make officers or psi soldiers. It will also prove useful against Berserkers giving you two shots on these dangerous enemies that will not trigger panic checks. It is not as good as Executioner in the early game, which is when this class adds the most value.
Covering Fire is not very good. If you get Suppression at SGT rank, it is likely to give you a free but low quality shot when suppressing. The overwatch build can also make use of this ability, but it is still only marginally valuable. Its worth noting that your target will be granted their cover bonus.
Opportunist
I highly value both Opportunist and Advanced Fire Control, which will remove the -30% aim penalty when shooting at moving targets. This usually amounts to 20+ aim, supposing the target is not moving through cover. Despite this large advantage, I am not over fond of the OW build for any soldier class, and discussed the limitations of overwatch fire at length in the Medic build.
With the full overwatch skill set the Medic will become a powerful overwatcher, with the potential to shoot multiple times in consecutive turns. But overwatching is not as effective in Long War, as it is in other versions of XCOM, because of concurrent overwatch fire, and enemies moving backwards during activation. In all versions of XCOM, including Long War, overwatch shots are not as valuable as directed shots, because they lack control, and can be diverted to less important targets, or to targets that are harder to hit. Overwatch shots are not even guaranteed to occur. When they do occur, most commonly during activation, it is likely that the enemy pod will be sufficiently softened up by overwatch fire from the entire squad, and they can be dispatched easily on the following turn.
Running an OW Infantry may seem contradictory with my lower valuation of the overwatch Medic/Gunner. But those classes make a larger sacrifice, turning down transformative abilities (Dense Smoke or Shredder/Heat) to pursue overwatching, whereas the Infantry class gives up the tank/crit builds.
Still, most players prefer Critfantry, and for good reason, they are great shooters that can do enormous damage, which can save you in a tough fight. However, if you are planning to use your Infantry as officers, they will often be using command (on the Pathfinder or DR operative) rather than shooting at the enemy. The Critfantry build has less valuable on officers than the OW build, because overwatching during pod activations doesn’t conflict with using command. Back up infantry officers are also commonly used on Exalt DR missions, in which overwatching is very effective.
Alternatives: Will to Survive or Aggression
Will to Survive is a great ability that can make the Infantry an effective tank. This role requires suppression to work, because Infantry are more effective at fighting when stationary. Suppression draws fire, and WtS mitigates damage. This is a great combination that I turn down on the Infantry class, because the Gunner gets those skills earlier, and one suppression tank is usually sufficient.
Aggression is great, and will help the Infantry guarantee crits on exposed enemies. For non-officers, this is the perk to select. Aggression, and the entire crit build, is a worthy alternative to my OW build which I believe has roughly equivalent value.
Ranger
This is a great skill for the Infantry because aside from adding damage, it functions as a poor man’s Lock N’ Load. When the rifle runs dry, instead of reloading and shooting, Ranger allows Infantry to shoot with the pistol more effectively. After which they can switch back to rifle and reload. Its still a reload plus a shot, but in reverse order and not quite as effective.
Alternatives: Deadeye or Suppression
I grab Deadeye on my Snipers and Shoguns, which sometimes feel insufficient. Flying cyberdiscs and heavy floaters can be quite deadly, and more Deadeye would help against those enemies. However, by the time those enemies start showing up, the Infantry are no longer in my line-up. I prefer building Infantry for immediate impact.
Suppression is great. Using the Infantry as a suppression tank works really well, but can be redundant if you are already use your Gunner for that role. Sometimes it is nice to have 2 suppression tanks, but usually it is not necessary. It is also expensive to provide iron will to all the soldiers of multiple classes.
Sharpshooter
This ability comes with +2 aim, making it shine a bit brighter. Extra crit is still good, even if you aren’t running the full crit build, especially with the Opportunist ability. When paired with Executioner, Sharpshooter enables the Infantry to take decent shots against wounded enemies behind full cover that would otherwise be poor at best.
Alternatives: Tactical Sense or Lock N’ Load
Tactical Sense is okay. Here is what I said about this ability in my Rocketeer build:
Tactical Sense is a decent ability, but if you are fielding MECs at mid game, the enemy will usually prefer to target them, instead of your Rocketeer, who is likely in solid cover, and further away. TacSense is a reasonable choice if you grabbed suppression at the last rank, and expect to draw fire.
Lock N’ Load is nice to have when picking either Suppression or Sentinel as the Infantry will burn through ammunition at a faster clip. I find that ammunition issues are largely eliminated by the completion of the Ammo Conservation project and the acquisition of Gauss weaponry. With the Ranger ability, even when running dry, the Infantry can still shoot and reload, albeit somewhat less effectively.
Sentinel
With Opportunist and Sentinel the Infantry will become an overwatching demon, demolishing enemies on activation. The Infantry will have the ability to take 4 shots on the first turn of an encounter, supposing the Infantry was on overwatch. With a gauss rifle and Ammo Conservation there will be one bullet left over on the following turn, allowing a shoot and reload; Highly efficient.
Alternatives: Resilience or Bring ‘Em On
Resilience is a very good perk for tanks. But without suppression, this build cannot draw enough fire to justify taking this ability.
Bring ‘Em On is very good, especially when paired with crit enhancing abilities such as Executioner, Aggression, Opportunist or Sharpshooter. My build has 3 of those abilities and so Bring ‘Em On will sing on this soldier. On the downside, BEO can be overkill much of the time, especially if you take VPT at the next rank. Also, Aggression is the most important ability for the crit build. Without it, BEO loses considerable value.
Vital Point Targeting
VPT is fantastic here, adding value with every shot. An overwatch Infantry can burn through ammo like few other soldiers, and extra damage is a fitting capper to this build.
Alternatives: Extra Conditioning or Rapid Fire
Extra Conditioning is good. This build will not be drawing enough fire to demand extra HP, and the small bonus aim isn’t as good as bonus damage.
Rapid Fire is a solid alternative but conflicts with the extreme ammunition consumption enabled by Sentinel and Light ‘Em Up. With Rapid Fire the Infantry can burn through 5 shots a turn, which is one too many, and leads to less efficient reloading. I’d rather have the extra damage on 4 shots, and avoid the aim penalty.
I think you're underrating infantry, because you don't build them for their best trick: Suppression + Lock&Load. Once Ammo Conservation gets invented, such an infantry can sit in heavy cover and slowly solo kill a Cyberdisk or (unmerged) Mechtoid with almost no risk, by alternating (Shoot->Suppress) and (Reload->Suppress). When the alien forces start to rely more on "bosses", the ability to have a single soldier who can lock down a single enemy forever becomes very very powerful.