200 of my 1,300 varieties are red fleshed and I always say Pink Parfait is one of my least favorites. Truly believe it is location, we are in SE Ohio (zone 6b) with hot humid summers that can have a lot of rain. Unless it is a nice cool dry fall then Pink Parfait just does not taste good here. For the rest of the Etter varieties that you mention Rubaiyat tastes alright at first but good when left to ripen as you said and ripens last for us. Grenadine is way more popular with our UPIc guests.
Pink Pearl was the first red fleshed apple I grafted back in the 1980’s and I used to say it was my favorite but it is suffers like Pink Parfait from too much heat and humidity. Red Devil, Alamata and Discovery are some of the favorite red fleshed apple varieties growing here, Hocking Hills Orchard.