It's a shame you don't want an RTT, because Original War is one of my favorite RTT games of all time, bar none. It has more in common with Command and Conquer than it does with the Total War series, or anything similar to that (in a sense that it is an isometric view, and the points below).
You can build bases, vehicles and whatnot, but the catch is in that game that you level up your soldiers in any of the four fields (soldier, mechanic, scientist, engineer) and when they die, they are gone for good (which is probably why it is an RTT rather than RTS). That may put people off who like to spawn hundreds of expendable soldiers but I love it.
But anyway, off of the top of my head (to name titles that others have not) I can think of Rise Of Nations, and Total Annihilation, both of those games are amazing, check them out.
In TA you are looking at having hundreds of units on-screen at once, if that does anything to sway you, but it is one of the older titles, pre-dating StarCraft.