Indeed, totally agree.
Infact, why not instead of the Sulibans, have the Orions as the mercenaries for hire, and instead of the Klingons being manipulated, have it be the Andorians.
And the aliens from Silent Enemy could have been the Romulans too, just have their spacesuits with tinted faceplates, it would have been a much better introduction to them than what we got in that stupid Minefield ep.
They could have revisited so many established races, given them back-stories and helped solidify the ongoing story of Enterprise without having to introduce a bunch of species we'd never heard of before and that have apparently been right next door to Earth the entire time throughout the 23rd and 24th centuries. Enterprise made space seem even more crowded than ever before.
I wished they'd stuck mostly to already established species, fleshing them out and showing how first contact with them would have been, species like the Trill, Bolians, those golden dwarfs from Journey to Babel, maybe even the Betazoids (since they're apparently pretty close to Earth, would have been interesting to see how humans and T'Pol would have reacted to a completely telepathic species).
A few of the introduced ones were pretty good though, such as the Xindi and Denobulans, I've no problem with a few new species being introduced, just the shear number of new ones was staggering.
And the TCW was badly thought out and executed.