Honestly, I think that it needs MORE than what I said, and it is still not enough, because battlemech have superior mobility and melee attack, and torso twist without spend weight on turret(although turret is good anyways).
It is true that Battletech universe puts mechs superior over vehicles, but I didn't deny it. I just want to discuss about the additional houserule to make the expensive fusion vehicles equal to mech, against the basic theory of the universe itself.
I don't think that mechs are need to be superior at all. After all, it is only a biped(or tripod/quad) tank, rather than use track/wheel/air cushion/rotor/ground effect to move. Walking, and having hands for some models, is the only unique feature of the battlemech. Thats ALL the difference, actually. Am I hate walkers? Not really, and actually I prefer them over vehicles very much. But I am not gone so far to intentially make the vehicles worse than the walkers. It is the matter of taste, not the matter of tier level. If there should a tier level, it should be ICE/Fuel Cell and Fusion engine, not by how it moves. What I want is both of them are coexist and the individual situation makes some of them better than the others, not simply declare that some kind among them is superior.
Well, what I expect them is not truly same unit, or what I need is just a legged unit. But I want them to be work as the same unit, an equal one unit in the lance, not the 'inferior' unit despite put the best effort to produce as much as making a battlemech. Making CVs even with the mech doesn't kicks mech from their place, and I never want that(because I like biped machines very much). It just provide us more reasonable combinations.
Accuracy buff seems mimimum effort to do that, for I think that they should better at ranged attack because they lacks melee attack. Then it can support the mechs behind. It is still not so gone so far as giving them more tonnage to weapon. Perhaps 'reduce' the tonnage for weapons NOT mounted on the turret seems doable, though, for I am always think that fixed weapon on the CV have little meaning other than fluff. It may makes so called 'tank destroyer' styled vehicles worth considering. Although I don't like turretless combat vehicles with a weapon personally.
Not allowing DHS seems only making the CV inferior to mechs, not because it is not possible in the reality of Battletech Universe, for aerospace fighters are actually use DHS without any problem. But, DHS and ignore non-energy heat source seems tradeoff and can't be combined. It is interesting to use the tank with same heat rule with mech, though, but it must also count every heat source as the mech does.
And among what I suggested, the internal part means simply combine internal with only one part(body). For now the internals of CV is divided to front/rear/left/right/turret(if it have one)/rotor, with the point 1/10 of its tonnage. But what I suggest is, remove all of them save for rotor and just make the internal of body, with the point of 1/5 of its tonnage, and still keep the rotor for VTOL.
For example, a 100 tons CV currently have 10 points on each front/rear/left/right, and turret if it have one. But with the suggestion, it only have 20 points of internal, and any damage breaching through any location directly damages it. So it is more durable against one particular direction, but still far from an invincible wall. It will be easier to record as well. And, 20 point of internal is still too weaker than a 100 tons mech's 31 point of internal on center torso either, so it can be increased as well, but consider how mechs are fell(usually they fells by destroyed gyro or engine, before it lost all the mandatory internal) it seems safe to leave the internal to 1/5 or 1/3.