We (the new RTR team) released the RTRVII:The Iberian Conflict mini-mod earlier this year and now are working on RTRVII:Fate of Empires. Check out the previews here: http://www.twcenter.net/forums/forumdisplay.php?f=26

If you want to play a grand campaign, ExRM (based on RTRPE) is a good one.

Another mod that's under development is Paeninsula Italica. It's in open beta now.