I'll never support or recommend unit caps, it completely screws over players that might want to bring unusual or small units, especially infantry.
Instead, I highly recommend discussing with your opponents beforehand, and implementing a looser rule, called "Don't bring a swarm, and I know that you know what I mean."
when you have a BV cap and a Unit cap, the outcome is a duel between identical units-in which case, you might as well just shuck the whole thing, pick one design for each side, and play out a duel.
YES, objective BV can screw up-someone can powergame it with a swarm. sure, that's possible. It becomes LESS possible if neither side knows what the map is going to look like before it starts, in addition to not knowing what the other guy is bringing. (and for hilarious fun, take two swarm players and pit them against each other, heheheheh.)
but here's the thing-and it's the same problem that eventually killed FSM as a concept that works.
take the hypothetical 17K bv. Now, what is the smallest force you can build with 17,000 bv? NOW, add in force limits, becuse that's going to push your numbers down, and your smaller number of units with more optimized stats, and optimized p/g scores will result just as surely as an unlimited by force composition game will allow somebody to game the system the other way with lots of disposable units.
I'm sorry but 0/0 p/g in an optimized Clan Assault 'mech on both sides, standing at medium range and rolling dice for four hours is
boring.Objective BV is all about "you don't know what you're facing, or how many, or what kind, you just have this number and whatever kinky tactics you want to try."
in my own experience, this tended to create game nights where the force with the
broadest coverage had the best chance, (presuming equal skill between players).
IOW a little of everything, or at least, everything put together with a purpose to cover the broadest range of scenarios. Hypespecialized units (that guy with the ultra-elite Clan pilot in his customized Clan Assault) sometimes do well, and sometimes that swarm guy with his Savannahsortie finds his key 'tactical asset' can't cross the wooded map and he's fighting crippled because he was leaning on a unit that has movement restrictions because it's cheap, or because it's vulnerable to Joe over there who's playing with thunder Lrms and indirect fire with a battery of light to medium weight artillery and spotters supporting his otherwise-3025 era lance.
The weird results are the ones you talk about weeks after the match, it's not the cookiecutter duels with ultraelites in widowmakers.