I like the idea of the package. I have even prepared a patch for GADU-GADU and TLEN (Polish IM).
I think package should be released
as alpha, then interface could change if necessary.
I think image servingis necessary - gifs should be served or similar to original gifs (different for each IM).
Besides DISABLED/ONLINE/OFFLINE status, there should be AWAY status.
Any documentation/examples "how to use it" would be also fine.