Personally I think this would make all the difference in the world to keeping the mechs from being bland and boring in the long term.
For what I mean when I say specialisation bonuses, I mean a percentage bonuses to a base skill or two for each mech, allowing interesting builds to be made but also showing off what a chassis is actually made for while still making it customisable.
For example, take the Longbow from Mechwarrior 4:Mercs. It was supposed to be by and large a long range support mech. If it came with a 5% boost to missile range per a certain skill (say Assault mechs or the Longbows own special skill), then it would be able to outrange everything to make up for its comparatively weak armor for an Assault mech.
Buuuuut! The beauty of that idea is that someone can pile on the tonnage to the Longbow and make it averagely defended against other mechs (at the cost of speed and used tonnage), then utilise its range bonus for something like Flack guns (or SRMs in this case), making the mech a surprise close range damage dealer even if suboptimal against others (as all machines would have a bonus to something and I'd expect a lot of assaults having a bonus to damage or resists) the pure shock factor could make it a useful bait mech for team tactics at the very least.
This is just a simple example, but I can see millions of uses for it, look at Eve:Online where I got the idea from. You could give speed, BACs or per sensor unit boosts directly to some scouts, ECM reload boosts to certain units like the MadCat and heat dissipation per sink bonuses to pure beam shooters. The idea would literally be to give a level bonus to every mecha.
Of course the reason you would do this over just increasing base stats would be the fact that to become optimum at a certain mech now needs some XP (or skills) as lots of these would be done on top of base stats as per skill level buffs.
Edited by Gen0, 16 June 2012 - 06:14 AM.