You can add a "doesn't matter" checkbox to fill any of the other groups... let you get a group faster but you just stfu if the group doesn't meet your special expectations, and good for everybody if you really don't care about that epeen/noepeen stuff.

and other advantage nobody would know if you wanted the DPS or not or if you just went there with a don't care check. so less prejudice.

Also i'm not sure that the maths would be as simple as 1/2 pools. Because with that choice, a lot of people who want to play for fun and not rushing everything may finally use the tool knowing they have a good chance to find people with the same state of mind. And less kicks and leave will surely make the grouping tool more efficient overall. (even if groups are formed slower). But probably people rather enter a group faster and kick and leave and whine during hours. sigh.