Hi,

I would start playing as a heal or tank at first because I have shorter queues.
Then I would need on dps jobs gear and still have shorter queues.

I don't see this happening.

That's why playing with friends, Free Company or members of a linkshell you play often with exists. You can talk about it, and usually solve any problems.
I do understand what you mean.

Maybe an option in party finder but everyone should be able to know before accepting to enter instance what everyone wants to roll on.