The payout minimum used to be 5 ITNS, now it is 50... that's an insane 10 times increase. Makes this pool entirely unpractical for me with a single CPU mining rig.

Ah bummer, try finding another pool with a lower payout. Sad thing is you would end up with 14+ stuck on hashvault, so maybe stick it out if you think you can get the other 35 needed. Good luck
Got stuck worth a day of mining pending (not that much, but still). Now I have to stick it out for another 8 to 14 days depending on the situation of the blockchain.