Well, there were a couple of time-based objectives but on Normal difficulty they weren't too obnoxious. There was some variety in objectives beyond just destroying bases (though usually this was at least a secondary objective in some fashion, maybe not outright bases but support posts where they're training reinforcements).
And yeah the unit cap is kinda lame, though it does take a while to hit I guess.
I just finished the GDF campaign in 11 hours. Missed a few optional objectives... for most of the missions they are impossible to miss but in a couple there are some counter-intuitive triggers you have to make to make them appear.
Gonna try the first one of the Dynasty campaign, which looks like it's classic C&C - parallel timelines instead of a continuation of the story.
RS3: UltimaSuende - CE Thread Zone
https://letterboxd.com/BMovieBro/