I think the Mobile SAM needs a reworking. They've lost about 50% on their bonus to Gunship attacking and they've also lost 20% of interception ability (or lost a small amount). The only new thing with Mobile SAMs that they have more strength.
So they need to be reworked on to be better... (or is this a consequence of the Next War Mod? Compare for me)
As for the Marines, I think they're fine as is. Although they could go with a bit more strength. I'm sure they'll go well next to Mech Infantry (Maybe Mech Infantry should be some sort of support unit, not a city defender. Perhaps a land APC?)
The Mobile SAM is fine... it has the exact same stats as the pre-BTS SAM, but with move 2 and more strength
The stats are
Str 18
Move 1
Intercept 40%
Gunship +75% (31.5)
To
Str 22
Move 2
Intercept 50%
Gunship+50% (33)
so it is slightly better against Gunships, it is Mobile (the big advantage) and stronger against everything else.
Marines and Paratroopers Are good for the Industrial Era, once you are fully in the Modern Era, Marines and Paratroopers are too weak and their special abilities not enough to justify building them.
So this thread is suggesting that we Keep the Marine and Paratrooper, but add a New Higher tech Unit that is the Upgrade for the Marine+Paratrooper. a unit that would appear around the time of Mech Infantry, Modern Armor, Mobile SAMs, Mobile Artillery (all the M units)
Which means at least
1. combining the abilities (Amphibious+Paradrop)[I'm proposing adding 2 range to the Paradrop as well]
2. Making them either Move 2 or Commando (to keep up with Modern units)
3. Adding on some Strength or some more abilities/bonuses (Str +4 v. Wood+Guer I v. + to Defense)to stay matching with Modern units
for Tech requirements I think we've seen a minimum of Advanced Flight + another tech in that range [or a tech that requires advanced Flight]
As for Cost, probably about the same cost as the Mech Infantry, + or - some.. depending on how good the unit is.