Tribes 1 had hundreds of maps and numerous variations of each dependent on game type. Out of those hundred, maybe 20-25 were actually playable, and only maybe 7 were really fun in 10 v 10 CTF (Raindance, Snowblind, Dangerous Crossing, Stonehenge, Rollercoaster, Hildebrant, Canyon Crusade) Some of these were default maps that came with the game, but they were all modified over time as game play changed. Right now I would say Zenith, Frostbyte, and Fallout are solid maps without a doubt and cater to slightly different play styles. I really like Stygian, but I haven't played a pickup on it yet so I don't really know if it needs any changes. Gorge is alright, but the oob grid is too close to the bases. I feel squished every time I play that map. Could use some smoothing in certain places as well. Core and Mirage have a lot of potential (seriously lots), but need some terrain smoothing and base changes to really become great. Blade run is a beast of its own, and if the terrain was just varied a bit from the long flat plains and the bases moved closer together, i think it would become a really great map. Forgotten has really awesome terrain and the bases are neat, but the giant half pipe in the middle really gimps the game play of that map. Nivo and moonshine are just too small for how fast the game has become to really be fun. they end up playing completely linearly and chasing is basically nonexistant unless a capper messes up or you get a lucky half map splash kill. I have yet to play ctf on elegiac or sleepwalker.
granted this is all my opinion. take it for what you will.