Only if it goes to the point that certain ones are being favored over others.
That's my only real problem with making it case-by-case. Activity's a pretty subjective thing, so if I tell someone that they can't pick up another character because I don't think they're active enough with the character(s) they already have when they think they are, how do I prove I'm not just playing favorites when, hey, I let Mun A pick up another character and s/he's only made two more posts than Mun B did over the last month.
I know I probably sound really paranoid, but I've run into the problem before in my other game -- not over this particular issue, but another one that was based on personal opinion. I'm not saying that it'd definitely happen here, I'd just rather avoid before it potentially does come up and I think the only real way to do that is to just have a set time limit. |D