personally i think both TR and NC will be very effective at taking bases, TR's rate of fire and acuracy at range will make them more suited to defence.
I think well organised attacks will consists of several stages, possibly an incursion by stealths, who kill key personelle and disable whateva defences they can.... they then lay low. The base would then be pummeled by tanks at long range (NCs tank would out peform most in this role). A large assult force would be airlifted to a series of rally points around the entrances during this time.. The assult force would then enter the base and overrun whateva resistance is left.
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