Couple of things to note:

Caster, melee, and ranged physical DPS all do the same thing: DPS. You should try to keep them roughly equal to each other (so our next classes should avoid melee DPS and drop another caster and/or range physical if any DPS at all), but you shouldn't compare them directly to the tanks or healers.

Standard groups are either: 1 tank, 1 healer, 2 DPS, or 2 tank, 2 healer, 4 DPS.

That is to say an equal amount of healers to tanks, and 2 DPS per tank, and that's the ratio we want. The one that parties are made in. IF ANYTHING, we should shoot for more tanks and healers than DPS to try to draw people into playing those roles to fill out parties more easily as most MMO players naturally gravitate toward DPS (this is for lots of reasons I don't feel like covering here).

However, we currently have 7 DPS to 3 tanks and 3 healers. That means our proper ratio for party filling is off by about a third of a class. To even it out you'd want 1 more DPS and one more of each tanks and healers. To err more toward the side of party filling you'd just put in the tanks and healers and leave the DPS alone.

That said, I don't really care what role red mage or blue mage or samurai fill. What I DO care about is if we just keep making all the 'favorite' classes into DPS we're going to end up going back to 30-45 minute DPS queue times for every roulette during prime time, and hours off prime time.