Problem is it'd mean that CCA and ISA would just dominate the queues even more than they do now, which the devs probably don't want. They put time and effort into making newer queues and would like more than some of the oldest PvE the game has (though both have been revamped more than once) to be played.
Edit:
Another option is to do the multiple-mark choice thing, but leave over-played easy to get marks (Omega for ISA and Nukara for CCA) without the option. A lot better than the recently floated in an interview with Geko idea pushing all queues into daily rotation (which would be bad if you need Rep marks for something not in rotation on the days you play).
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Edit:
Another option is to do the multiple-mark choice thing, but leave over-played easy to get marks (Omega for ISA and Nukara for CCA) without the option. A lot better than the recently floated in an interview with Geko idea pushing all queues into daily rotation (which would be bad if you need Rep marks for something not in rotation on the days you play).