TRO:3025, in their introduction to Assault Mechs says that there are "very few well designed assault mechs" saying that designers had focused mainly on the classes capabilities in physical combat and seemed to suggest the TRO authors hopes for more effective assault mechs in the future.
Now, IIRC, there were about 10 assault mechs listed in TRO: 3025.
Of these, seven of the ten seemed to be considered good, solid, well conceived and built fighting machines.
The only really "bad" assault mechs were the Charger, Banshee, and probably the Goliath.
So what happened to all the "badly designed" assault mechs that the author seems to imply exist.
Let´s look at it...
Awesome and Stalker are very solid designs.
Atlas and BattleMaster are a little short - okay okay, VERY short - on long-range firepower, and the Victor doesn´t have any at all. That sort of thing is forgivable in the Hunchback, because it´s cheap and doesn´t have the mass for good long-range weapons in addition to the short-range punch - but it´s NOT forgivable in an assault-class design. The Atlas at least has the massive armor needed to get close enough for its main weapons, and the LRM-20 cannot be neglected, either.
The Cyclops has all the problems of the Atlas and BattleMaster, with the addition of also having the same armor as the Hunchback (which is little more than half the Cyclops´ weight).
The Zeus okay(ish), but it´s a bit of a "neither this nor that" design - neither the massive long-range firepower of the Awesome, nor the massive short-range firepower of most other assault-class design. Neither good nor bad, I´d say.
The Goliath lacks effective short-range weapons, and has the firing arc problems that all quads share - though that usually isn´t a great problem at long range. Its long-range firepower isn´t great, either, but still better at 16-21 hexes than any stock assault other than the Awesome.
The Charger and Banshee... the less said, the better. Now, the BNC-3S, that´s a great design on par with the Awesome and Stalker, though.
So, we have 2 terrible designs (stock Charger and Banshee), 3 problematic designs (Cyclops, BattleMaster, Victor), 3 useful designs (Zeus, Goliath, Atlas) and 2 very good designs (Awesome, Stalker).
Compare that to the heavies, where there are three terrible designs (JagerMech, Bombardier, Rifleman) out of more than twice as many models - and these three are not nearly as terrible, relative to the others, as the Charger and Banshee.