[instinctpt1]

Sql or vault acc to people's need
Prefix for chat acc to ranks configurable through cvar
Separate add-on to the xp plugin for bonus weapons ( some people like these stuffs )

Introduce a rankings chart ( motd ) showing rankings of top 10 players along with their ranks like top15 plugin

You can try all this if you are sure you can go ahead of serfreeman's AES