I'm glad the only thing you have to complain about is balance!
That means we're doing well so far because there could be many actual game-breaking bugs instead.
As I had more fun with MWLL than with most retail games I tried last year... I'd even pay for that beta. Sure its still rough in many areas and alot of work still needs to be done. Buts its a) mechwarrior and b) already fun.
Anyway, problem is not that its a "combined arms" game. Problem is that mechs are rather WEAK right now. This will prolly change with the next patches anyway, but it just doesnt feel right. Tanks are cheap, Lasertanks outperform Mechs below their own tonnage easily and assault mechs that cost twice as much still explode if you surprise them or or focus fire with multiple tanks. They are smaller targets and less likely to be spotted.
Aerospace greatly rewards veteran pilots, offering great tactics view, invulnerability to most weapons and easy kills against pretty much everything that isnt another aircraft.
BAs by itself arent that special, but shine if someone ejects in time and it basicly like that megaman boss.. you kill him, then his body dies and you still have to fight his head which still kicks bottom. Its frustrating if you win a close battle but then lose your mech against the minimech inside the other mech. Beside that they are perfectly fine, at least if all weapons would work against them. Full SRM blast in your face? Didnt even hurt.
And mechs? Big easy targets that often have no roll to fulfill in a match and are overpriced.
Or another way to look at it:
Aerospace
+ protected by lag/ping
+ needs hardcounter or you suffer badly
+ direct counter to groups of ground targets, ground targets, heavy ground targets or air targets
BA
+ protected by lag/ping
+ needs counters or you suffer
+ direct counter to heavy/slow mechs, single mechs and mechs without anti infantry weapons
Mech
- not protected by lag/ping
- anything hurts you or directly counters you
- does not directly counter specific units
You cannot call it "combined arms balance" if some units like aircraft needs specific counters (anti air fighters that need to WIN the air battle) or your whole team dies horribly, while other units do not require any counters and do not counter anything. Its like playing ROCK-PAPER-SCISSORS without ROCKS. You can pick Paper or Scissors. Paper counter Scissors. Paper and Paper cancel each other out. Scissors is meaningless. Well.. what will you pick?
If air would counter mechs, mech would counter tanks, tanks would counter air -- as a rough idea, that combined arms thingy would make sense. Right now it doesnt. I like the idea of tanks being low/mid budget specialists that can either deal well with BA, Air or Mechs/Tanks (or go hybrid by being okay against both mechs and air or mechs and ba). I also like the role BA plays, beside the ejects as final boss form thingy. But air costs not enough, does require too specific counters AND is sick powerful if no counters arround. So what is there for Mechs, beside the NAME OF THE GAME? They cover the tonnage above tanks right now. Thats their roll, thats what they add to the batte. More tonnage than tanks.
Design-wise I'd like to see Mechs as the primary ground force because of diversity, customization and obviously also tonnage. Even manoeuvrability, as 40k books tricked me into believing that walkers can deal better with difficult terrain than normal vehicles (which is not the case in MWLL right now: "Oh shit, its a small rock on the road! The path is blocked! All units head back to base for debriefing!"). Tanks should obviously cover low budget armored vehicles and support. Dedicated AA? Tanks. Artillery? Mainly tanks. Jammer, Scanner, whatever-support-vehicle? Tanks.
Of course its no black/white thinking. Mechs an take those roles, too (to a certain degree, tanks with better fire angle will always cover air units better IMO; cheaper artillery is also better as most of the mechs advantages are void if you are nowhere near the battle) and there can be heavy tanks that are expensive and take the role of mechs. But that shouldnt be the primary objective.
BA obviously are a special case, being a guerilla distraction special force that is strong at harassment, able to strike against weakened or imporant targets without drawing attention and powerful against single or wounded mechs that cannot keep up with their agility. This is a way to bring infantry feeling to a mech game without scores or worthless cannonfodder being killed by every laser blast. It serves no "important" role, but has a niche that provides a way of playing that adds to the feeling/fun of the game.
Aircraft (or "air support" as the ground forces always call in air support and not the flying army) with bombers and fighters is a small battlefield on its own, bombers or better: anti ground flyers provide devastating area damage that deals with otherwise unkillable armies and heavy targets such powerful mechs (top of the ground foodchain) or stationary targets like a BASE, a DROPSHIP maybe, etc. Fighters on the other hand are rather weak against ground targets, even thou they can deal decent damage against smaller targets with less armor. Their primary objective is to gain air superiority. Also bombers usually fly at high altitude because everything else gets them killed. That also means they hit shit without beacons or so. Or at least I thought thats the reason it works like that in every movie or game. In MWLL that isnt case. You fly high to get close, swoop down for a easy kills and fly away again into safety. Low risk. High reward.
Anyway, enough rambling.. im tired.