this is unacceptable and is actually against the ToS.
Where exactly does the ToS cover players choosing to equip the gear THEY want to use before queuing for a duty? Is it an exploit, not really because that's how the system currently works and has done for a long time. You can do it with most roulettes to somewhat effect the outcome, but it's not guaranteed. Besides if there is content you need to do, don't rely on a roulette to give it to you.

On a side note we do need min ilvl for leveling duties (because of undergeared issues), but that's it.