A large number of suggestions:
-Possibility of convert whitelist to blacklist (I did this for a plugin, something like a ban with custom message
)
-Add a cvar for change msg of kick, For example: "only people of X clan"
-Add steamtools support for allow people of X steam group, or maybe allow people with X clan tag (allow o disallow, remember first suggestion)
-Add natives for developers, for example (OnClientKickForWhitelist) or (IsClientInList)
-Add option of ban 1 minute to people kicked to prevent that they reconnect several times (spam)
-Add option for log kick in a file
If you add all that, this plugin would go from being used by a few people ,to being used for several people (perhaps myself included)