I'll leave the list cleaning to you, boss. I was about to do so myself, but since you're already on top of it....
I added a couple new bans on odd e-mail accounts used to register by likely bots. Unless people think that "_____@free.fr" and/or "_____@wp.pl" are addresses that real live people might actually make use of.

A lot of the bots also seem to use "_____@yahoo.co.uk" addresses, but since that IS likely be used by non-bots as well, I'm reluctant to slam that one.
Upon further review, I've also put a ban on registrations from the "internetserviceteam.com" hostname. That's a confirmed group of do-no-gooders that aren't necessarily bots themselves, but pave the way for bots to follow them in droves. I can't find anything that suggests valid users should be using that hostname.