My personal favorites are ControlCraft and Control Craft 2, but those are not universally popular. Some other popular strategy games I can recommend are Royal Squad and Sword & Spoon. None of them are tower defense games.
ControlCraft reminds me a little of Solarmax and another game I can't seem to remember, except CC is better.
It's a shame that there are a lot of games on this site that are incredibly awesome, but don't have the recognition that they deserve.
Although they're probably not what you're after, I tend to think these games are pretty awesome.
Sentry Knight: Conquest - http://armorgames.com/play/17700/sentry-knight-conquest
Civilizations Wars - http://armorgames.com/play/5151/civilizations-wars
Battlegrounds 2: http://armorgames.com/play/765/battlegrounds-2
Deadly Neighbors 2: http://armorgames.com/play/13873/deadly-neighbors-2
They're probably not the best of games, but I tend to enjoy them more than I should (Didn't want to add popular games that you've heard of, except for SK, that's too awesome not to use).
Good luck and have fun with enjoying yourself. ^-^
P.S I don't know how to do that amazing trick Arm can do, so sorry about that. :'(
