As I recall, Trinity used to have a sweet canyon airbase battle as well with spawns in the middle and two air bases that spawned into it that had some amazing air and ground battles. Later versions of the map had the canyon removed.
The base horders got upset that everyone wanted to play in the canyon and fight and not roll bases so they complained for long enough to have the map nerfed, and then eventually removed. 
It had nothing to do with people GVing, Compello and CraterMA (the AH2 version, before the crater got filled with dense jungle) probably had more of that than Trinity did. The problem with Trinity was the literally 40,000 foot-high mountains that made the land fronts completely impassable for aircraft - even where there were passes, many of them were so high a C-47 couldn't practically get through them, and of course there were no GV spawns. It didn't help that most of the coastal bases had GV spawns from the interior to the coast but not the other way around, which made moving inland close to impossible WITHOUT an irresistible horde. With that and the very wide oceans on the margins you'd always see one or two bases captured and then the attackers inevitably driven back into the sea with no support from the rear and no way to move forward. Maps with things to do other than capture fields are fine; maps where the field capture game becomes impossible without a 3-1 numerical advantage are not.
Trinity would be a fine map (if the player base grows enough to support large maps again) if the height of all the mountains were halved (really, 20k mountains with 6-8k passes are plenty high) and a few GV spawns added so all ground movement wasn't stopped at the coast. If anyone was considering updating it for AH3 I would
strongly recommend reducing the terrain height all over. The canyon battle was fun, but unfortunately, it really favored one side over the others, and there was no equivalent on either of the other fronts.
(And 40k is not an exaggeration - I tried climbing above the peaks near that GV spawn in a light P-51 once and gave up at 38k. There was ginormous vertical cliff - with the
base of the cliff at 5k or so - in the canyon leading to that spawn and I don't think I ever saw a goon make it over that cliff.)