I've been playing CoH on and off constantly for this exact reason. I play on Everlasting, and while /ignore is very useful, sometimes hanging out in Pocket D or RPing or whatever, some drama-stirrers will just be there and you can't avoid the people you're interacting with crossing paths with them, outside of just suggesting they avoid them or move location. Doesn't always work though. It's certainly not as bad as some other communities, but it can be slightly annoying at times.