Going to assume
@Taghkanic, that you, too, are a winning player in this game, and wish to keep playing there (and thus, keep it alive).
If you want to keep this game light and loose (and profitable) think the
last thing you want to do is suggest drawing for seats.
First of all, it adds a bunch of complications. Do you only draw for first X players? Or for everyone who's indicated they'll show?
Just like what happens in classrooms without assigned seats, or open offices without assigned seats, is that folks pretty quickly pick spots and stick with them. Nothing to do with collusion, everything to do with human nature.
Add in the fact that these guys are good friends for decades and
of course they might like to sit next to each other.
Healthy, lucrative cash games are delicate organisms, like orchids lol. You need to put in a bit of effort to keep them healthy, and it's not hard to inadvertently kill them off! Suggesting picking seats is not the way to go. If they are colluding somehow, they'll still find a way to do it, and if they aren't, you've suggested making the game more complicated/annoying, and possibly insinuated you don't trust how things have been run up until now.