Ranger models would need the helmet of the lieutenant to make it more recognizable, plus the rangers have ranger decals on their helmet that would look out of place in a regular squad.
You could reduce the cost for sprint and flares since they would be locked behind the Veteran Sergeant upgrade, but the idea of locking the abilities behind the Sergeant was deliberate. I wanted to tie those abilities to the Sergeant for several reasons:
1. Encourage the use of the Sergeant, get the guy, get the abilities.
2. Prevent double BAR squads from sprinting up to MGs and being too strong. By making the Sergeant cost you a weapon slot you can now only have one BAR while sprinting up to a weapon team. This makes it less punishing to be on the receiving end of sprinting Riflemen.
3. Encourage use of grenade tech rather than BAR tech. Smoke, sprint and frag would be even more viable with an extra man to take damage and make aggressive grenade use less risky to try, but still expensive to pull off. This harkens back to the vCoH days of Riflemen grenade flanks being the top players US bread and butter tactic. Go watch some old DevM games from the Sunday night fights games to see what I mean.
Models can be reskinned here, but not remade. Decals on the ranger model are a non-issue requiring only a texture change.
6-man Rifle squads would be far more alluring than the tech-locked 120 munition sink double BARs are, and Fire Up has already historically mostly been good for getting in close to throw a grenade, as you say. This all without a gateway upgrade that ultimately makes the upgrade less accessible. I wouldn't be totally and completely opposed to this veteran sergeant idea but I don't think I really like the idea of it being required for all these upgrades.
(on a sidenote: is it possible to fix the scoped garand animation? just looks off that the pathfinders cycle them like bolt action rifles after each shot.)
It is in fact an incredibly easy fix that only requires changing the current wind-down time (1.3) to a value below 0.25 and moving the remainder time to cooldown or something. (Or, honestly, nixing it entirely, since the Pathfinder Garand is already atrociously bad compared to the equivalent JLI G43 in every way.) Why it has never been fixed as a QOL change is beyond me
The same issue is present with weapon crew M1 Garands. It requires only the exact same fix. (Though to be honest, weapon crews should be using M1 Carbines anyway...)
On a last note, I really don't want weapon upgrades for riflemen considering this is the RIFLE COMPANY. Not CARBINE COMPANY, SMG COMPANY, or MARKSMAN RIFLE COMPANY.
Fire Up benefits Riflemen, and now that the debuff is gone it's actually somewhat decent.
Flares benefit Riflemen, and even though it's still expensive as shit it can be useful
If we were to give one more thing to Riflemen here I'd let them shoot smoke grenades like they used to be able to do. If we were to add a unit it'd be the M3 or M5 Halftrack to make it easier to transport and reinforce Riflemen in the field. No more new tanks, no pathfinders, no sniper, no pershing. Rifle Company, for Riflemen.
Churchill needs more nerfs. Just came back from watching the Banace preview tournament and that Churchill spam was so OP 
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