I would appreciate getting a bigger sticky mailbox quota and a higher limit for the auto deletion for supporters' sticky mail. I'd even pay a higher membership fee for such a feature. Disk space is dirt cheap these days ...
Another feature request: forwarding/exporting the sticky mails to a mail account is nice. Having the sticky titles as email subjects then would be cool. Having them time stamped too would be awesome.
Just in case you're getting bored, Brett. ;)