As far as graphics are concerned - it's kinda what we've seen in some recent threads already in image examples and my opinion stays the same:
Paperdolls only if someone will make lot of frames - one for every direction - for every sprite.
Mesh is a nice idea, especially for mechs. Of course, more detailed and scaled models would be needed as a test one looks like made of bricks. But for test - that's alright.
Maybe combination of those, like someone already suggested - detailed, nice paperdolls for people and.. well.. detailed and nice 3d mechas.
I still see some portraits that seem to not fit the canon much and do look completely unlike the others but generally I tend to find comparable, good looking portraits most often.
Also, some look great but kinda blurry - strange I didn't notice that before - like por_m_mechanic(-U-). Very good sprite but it and several others (presumably by the same artist) could use more sharp lines and shading.. although on the second though, maybe it should be left as it is as well, looks good enough.
Played for some time, no bugs found yet, no crashes as well. We'll see how it'll go in the future.