I had the most intense battles with my brother, even well into our 30s when we only met a few times a year.
It is sad that there never really was a successor that was as good. They could have lifted the 255 units limit, made the game more balanced, added a few more maps and units (but not too many), enhace the graphics (but keep it 2.5D, I do not want 3D in this kind of games) and make connectivity easier.
Cavedog released a fantasy game after that, which I wanted to like, but it was crap. And the Command & Conquer games were never for me. Tried them but never felt them.
Supreme Commander was that follow up. Basically the same team as worked on TA, making more or less the same game but with larger maps and higher unit counts.
I've got it. For me, I can't hope to beat the AI using low tech spam to grab wide open resources. But when resources aren't to scattered I almost always win against the AI.