Thanks for the comments, they will really help.
First of all, the grass texture. The reason I chose it because its overall color fits in well with the atmosphere I'm trying to create. I also don't like it when they use textures like this:

IMO, that's not much better. About what Julz said, that is exactly why I haven't used bloom until now. I need a bloom that only blurs/brightens the bright, white parts. Sylex bloom blurs too much, Ogre bloom brightens too much, etc. What I really want is something like the HL2 HDR:
http://www.bit-tech.net/content_images/lost_coast_screens/15b.jpgAbout shadows, I will NOT use stencil shadows for trees that will never move. It is unnecessary. If I use shadows they will be lightmapped onto the terrain. I have tried to use ventilators unfinished plugin, but unfortunately for some reason trying to open it brings up a list of errors.
The terrain is lightmapped for its own shadows, I could increase the contrast to make this more obvious. The same with the trees, ingame you can tell the difference between the sunny side and the dark side, but the ambient is pretty high so you can't tell from screens. Once again, I could lower the ambient of the individual trees through a material.
I think I've covered everything (that's a lot of issues for a simple terrain!). Once again, thanks for the comments.