redwing said:
I'm considering creating several homebrew feats that give additional advantage for tactics used in combat (height advantage, etc)
Being on higher ground gives a +1 bonus to melee attacks, and I think a bonus to range increment equal to the height difference, though I'm not sure about that. I am certainly a fan of tactical feats, but many good tactical options already exist in the game; see tables 8-5 and 8-6 on page 151 of the 3.5 PH for other bonuses.
If you do come up with some tactical feats, be sure to post them here; I love feats, especially tactical ones.
If you want more books on strategy, you could pick up
Roots of Strategy, edited by T. R. Phillips; it has Sun Tzu, Vegetius (trenches must always be an odd number of feet wide?), De Saxe, Frederick the Great, and Napolean. I haven't finished it, but it certainly looks interesting. I have other books on strategy, which I'm going to start on after I finish
Jonathan Strange and Mr. Norrel. These books tend to be advice to commanders and such however; you sound more like you would want books on sword-fighting or martial arts (of which sword-fighting is a sub-category, but eh), as they might contain more tactical information. You could try
The Book of Five Rings by Miyamoto Musashi, which is about sword-fighting but also tries to expand the ideas to armies; it's been a while so I don't remember how well it does that.