At first I thought this was going to be a thread about lag.

Well, to echo the advice given here, and even though it probably sounds like lame advice, you just have to "get better" in order to overcome cheap tactics online. Online fighting games can be pretty competitive; if you want to just chill and have fun matches it's best to play with friends or find a local arcade.

I've played Soul Calibur IV and UFC Undisputed, two of the games mentioned, on Xbox Live, and I have received precisely three messages. All of them congratulating me on my victory and telling me I am good.
The people on XBL are pretty courteous to me too. I often get a GG message or usually always a response to one of my own.

But I enjoy playing online because I believe it makes me a better player,
I agree. I don't think I'd ever be as good as I am at BlazBlue if I wasn't forced to get better from online competition. I'm a pretty average player, but I'm still way better than I'd try to be just playing "for fun", and for that I'm grateful for online play.