Try out all the races- they all play differently, and lend themselves to different strategies. +Econ (incredibly helpful) and +Morale make doing everything else easier. Terrans excel at diplomacy and influence, the Korath rock at taking worlds, the Yor have great production, Korx and Krynn have a ton of money, Altarians are great researchers, etc.
I've found the Krynn are quite easy to play due to having such a strong economy. I hate their super ability, though...
Above all, trying out a different race on a different map can make for a different game requiring new strategies, which means a lot more fun for you! And if you've got TA, the unique tech trees means trying a different race can be like playing a completely new game.