So I've had a few ideas for some terrains, and decided to give it a go. And I feel like the terrain editor itself is the biggest impediment to getting new terrains.
So, here's what I can think of to improve it. And if there are already these options in place, and I simply couldn't find them, perhaps a simplified UI is in order.
1) Whole map view. I found I couldn't easily get a sense of where any piece of land was in relation to the rest of the map. This resulted in, we'll, some pretty funny looking islands and peninsulas.
2) Add land at the scale of the entire map. The size of the brush really felt annoying. I couldn't just paint in a great big swath of land for my main land structures, and working within the confines was exacerbated by the issue addressed by my first point.
3) in-game view mode. Showing field icons, spawns, radar, etc as they would appear in game on the clipboard.
4) While not a terrain editor issue, I would like HTC to reconsider their policy on custom objects and bridges in MA maps. Perhaps let us submit custom objects for HTC approval along with our maps.