okay number of host may be a no can do, but your possible list have not been implemented.

5. [blocking ip addresses on search] definately not - it blocks chat. that's all it does.
filtering out bot spammer ip addresses would help a lot.
of course the spammer wouldn't want the rest of us to be able to tune him out... but then the rest of us could careless what spammers want. possible yes, implemented, no.

3.[search host for their files] would be useful on spammer bots too. possible yes [used to be included] - implemented absolutely not.