I prefer Liliana to Garruk as an end game threat. And I really like the green Cavalier. I would play this more as a midrange value build, so less cheap creatures. For aggro I'd probably go mono green.

i was planning originally to go mono green aggro, until i realized that splashing black for removal (mainly assassin's trophy) would be helpful, seeing as how green seems to run low in that department

I'm not sure I'd be playing any removal in an aggro deck, unless the removal could also go face (Shock & co). An if removal is needed there are some green fight spells. Assassin's Trophy is really good but giving mana to a control deck means they can play their board wipe / end game threat earlier which may be bad :|