[@Mahz] My suggestion would do nothing more than insert a link to the post where the character sheet is held. The GM could assign such links as they see fit. Implementing anything further would likely take quite a bit of effort, but a system like this seems to me to be little more than inserting a couple of URLs (I'm not a website coder, so I could totally be wrong). As a really rough mockup:

[img]http://i.imgur.com/YkYmH1m.png[/img]
[img]http://i.imgur.com/bHFyrVL.png[/img]