Last.fm isn't really expanding their API unfortunately. You can however see Last.fm stats in the main artist/album/track commands.
As for spammyness, I'm aware this is an issue. For non-bot channels I recommend using .togglecommand and enabling just a few specific commands, and setting a small embed mode so .fm commands don't take up too much space in chat.
Just one admin's opinion, but I think the bot spam thing is more a matter of server etiquette than anything. Sure, I'm all for #bot-spam channels, but nobody looks at those unless they're using it, so it's not very useful for things like sharing last.fm stats. I'd much rather people use it sensibly in a #music channel.
Also thanks for your work, while I dislike the spammyness of it, that's on the server owners (main server I'm on limits it to one bot channel)