I'd really like to see a theme templating engine for zabbix a bit more robust. Like smarty for instance. (http://www.smarty.net/)

This would make it much nicer for people to develop themes for zabbix and create their own frontends.

A lot of people don't use zabbix because they don't like the UI look. Or they'll actually use API calls to gather graphs, etc. I'd love to see this pushed forward!