There's a lot said (pro and con) about "game balance", and I think that most of the arguments in the pro column use 'character-power-equanimity' as a benchmark. I sit pretty comfortably in the con column here. I like the fact that there's not a strict 1:1 relationship between benefits/restrictions, possibilities/limitations of early D&D classes (and races if they are decoupled in that version).
The idea that a 4th level thief should be (by some metric I don't think I've understood) 'just as good' in some way as a 4th level Cleric/Fighter/etc is. In the end, I don't get it. Different classes are different...
The thought process leading up to this match up was to open up the PHB Attacks/round for fighters to the other classes too. On an abstract level, I like it
...but does this 'rob' the fighting man of something too iconic, class defining? I dunno - not so much for me. Fighting men will still be more effective in their attacks (to-hit progression, strength bonuses, etc) than the other classes, and I like to think of thieves and assassins (especially) as being more 'fighter-ly'... Moreover, fighters have the 'attack as many <1 HD as levels' thing which no other classes get... I dunno - just an idea, something nice to have around if some 12th level wizard thinks they should have gotten better at fending scaly goblins off with their dagger... at least I'll have a little logic already in place...
So, anyway - balance vs trade off? I doubt that anyone chooses their character's class based solely on the criteria of multiple attacks at higher level.
Ugh. another ramble.