(yes, I am fully aware that characters cannot be recruited while offline)
The new Blizzard UI for applying characters is kinda blah.
It would be "nice" if there were at least a green/red light next to the applicants to mark who is online/offline (and sort them).
It would also be nice if previous applicants remained (until declined/removed), so that you were able to see what guild they joined, and whether pursuing them would be worthwhile.
And hey, while you're at it... maybe some support for people already in guilds (but wanting to view recruiting guilds, and/or apply to guilds using this addon) could be added.
Theres a lot more that the blizzard guild tool is missing, IMO, but at least these require little modification to the current UI.