So lots of shows here I would bring up but have already been mentioned repeatedly. So I'm going to mention two nobody else has.
BattleTech (1993)
Yes, this WAS a 90's show believe it or not. Yes there's a few errors in research made. Yes, the show isn't exactly a 100% reflection of the BattleTech board game. However, for it's time (and even today) it still holds up to a degree. It even says a lot that the events of the show were integrated into BattleTech Canon (namely, Adam Steiner got a role during the Word of Blake stuff in later years, and there was at least one BattleTech sourcebook devoted to the 1st Summerset Strikers).
Exo Squad (also 1993)
I should start by saying I'm not a big fan of this one. I think like SWAT Kats and a few other shows I put on my "not dated very well" list, it's something I have to have seen at the time. For that, you can blame my folks not getting Cable until I was in Secondary School, and furthermore I was British - I don't think Exo Squad was ever broadcast over here because of our rather Draconian stance on censorship at the time (quick fact - the Teenage Mutant Ninja Turtles over here were called the Teenage Mutant Hero Turtles instead at the time, because of some perceived violence around the word of something because Britain is a country that feeds on stupidity and misery).
Anyway, but for it being extremely heavy handed in it's allegory (the antagonists are so Nazi Germany it hurts) and it's rather unwieldy characterization, I will acknowledge this was probably the spiritual Predecessor to Roughnecks: Starship Troopers Chronicles (which I DID get to see as a 90's Kid).
Also, not sure if these count or not, but why have Shadow Raiders and (the original) Max Steel gone unmentioned? X3