I use mostly size 14 but sometimes a 12 is the ticket. I rarely use 16 or 10, but they do have their place. Note this info is only for mtn fishing. On tailwaters I rarely use a BH Prince unless I'm on the Clinch or Hiwassee where they can be good in large sizes at times.
I came up with my own Yellow Sally recipe. I don't know if it will work we'll see. Yellow thread, some yellow dubbing in sparse layers, and Yellow Elk Hair. I tie this in a small 16 since many Yellow Sally's I've seen on Little River are small.
The hare's ear parachute has consistently produced for me in park and other mtn streams. Depending on the time of year, I will start with a match for the current hatch, but end up fishing the HEP at one point or another during the day.
My two cents