Perhaps if you donate, your ignore button can be renamed to "Ban User".
I think you've hit on something.
Members can sponsor certain functionality - for example, for a $25 donation, one could sponsor a smiley for a year. Highlight on the smiley, and you might see something like this:
"This smiley is brought to you today by Assclown", or "Assclown smiley at Nats2playoffs smiley registry"