Like on monster, make it so donors can make mystcraft worlds, even if its once a week or something like that.
I'm going to Vote no, not because it would be a Donor only thing, but because of the sheer volume of Donators playing the server. Think of it this way, the more people who actually use mystcraft for this feature will probably cause a TPS sink for each realm loaded. If done in a high amount there could be performance issues that generally lead to crashes and unneeded entity wipes.
