FWIW, I'd like to stick with a classic combo and that '70s/'80s curved "Illini" helmet logo. What I'd really like, of course, is completely ignoring our unis (as the top programs do) and instead simply put a winning product on the field regularly using classic unis. (Insert GIF of Abe Simpson raging at cloud here.)
I really liked the unis from '82 when the Illini finally began to climb back into relevance for the first time since the mid-'60s. Below are a couple clips from an SI article about the '82 OSU game (which we lost). I like the orange numerals with white outline, the classic pants, and my favorite Illini helmet design.
In '83 they went to white numerals with orange outline, which I didn't like as much, though I liked the slightly thicker blue helmet stripe. (And I could do without that blue-on-blue scheme.) Below the '82 photos I've included an SI photo of that uni from '83 featuring my former next-door neighbor in Snyder Hall, Craig Swoope (Mike Heaven was his bunk-mate; nice guys), drilling a Michigan RB in that glorious 1983 victory that fairly well cemented the BT title and RB trip for the Illini. Then I've added Thomas Rooks diving for a TD in that game. Just because.
I liked the Mackovic-era redesign, tho' that NY Giants "Illinois" on the helmet bugged me because it was a derivative design (that's why I prefer that curved "Illini," which is original) As others have noted, those Zook-era unis were great, too. Orange helmet-blue jersey, orange or white pants. Stick with that at home and sub in an orange jersey occasionally and I'd be happy.
And then, please, win more often than not.