Well, I don't know what are generally accepted theories about Alice's psychopathicity. Here are my conclusions.
OK, for first let's assume that Wonderland is something like a video game, a virtual reality or a lucid dream. Here, we can do all we want, disregarding consequences (but Alice would face SERIOUS consequences when dying in Wonderland, like being in catatonia for the rest of her life). Now we need to remind ourselves, how nice it was to rip and tear enemies in games like Doom (espiecially with Brutal Doom mod ^ ^) or God of War. It's rather hard to find someone, who saddened after serving fatality to random monster in GoW. Now let's imagine that we can do all of that in mentioned virtual reality created in our mind (lucid dream for example). Who would have resisted using such opportunity? Not many people for sure.
When it comes to Alice, it's clearly shown that she enjoys killing demonic rabble. HOWEVER it should be noted, that - unlike people playing video games - she's not doing this for fun. As we know, she was somewhat forced to use brutal force in Wonderland. In the first game, defeating Queen of Hearts was the only way for Alice to cure herself from mental disease (which packed her into Rutledge Asylum for almost ten years). In the second game, her "butcher strolls" through Wonderland led her to the shocking truth about Bumby (he killed Alice's whole family, wanted to erase her memory and was changing children into prostitutes, previously erasing their personality) and to gather up to push the guy into railway.
It's worth noticing, that despite the massacre Alice was doing in Wonderland, in real world she's a (almost) normal young woman. She doesn't look like she want to kill some random person, just like sane player won't be shooting people after playing Doom.
Alice didn't even wanted to kill Bumby. She wanted to pack him in a jail instead. Only when the bastard informed her about the misery of her situation, she finally gathered up to bring justice herself... in the least violent way (sort of).
So that's all.