I'm fairly certain that all minis from a single continuum are the same, although there's one sort-of-exception. There are five different minis for Avatar: The Last Airbender. As far as I know, any M-e fic, regardless of the original work it's based on, will use mini-Balrogs.

However, I'm still rather new, so an older Boarder might know of other exceptions or loopholes.

Speaking of being new, have you looked at our Sib Houses? We have an article on the wiki; basically, an older PPCer will "adopt" a new one, to help them learn their way around the community. My personal Big Sib is Iximaz. We exchanged email addresses, and that's about all you have to do. Are you interested?