I share your pain with the water level fluctuations, mine dropped 3' this summer. It would have dropped more, but I ran the well into the pond for a while to keep the level up. Since I drained that pipe for the winter, it's dropped another 8" in the past 2 weeks.
What slope are your pond banks, and what have you planted for erosion control? I'm guessing that they'll bounce from 1 ac to 5/8 ac depending on the time of the year. Like me, if you want to have a dock it'll have to be a floating one due to the water fluctuations. I'm guessing that you probably could go 10x more on the RES stocking, but I'll leave that up to someone that has better knowledge on stocking rates than I have. 50 RES in an acre pond aren't very many, and if you don't release the ones that you catch, they could be wiped out pretty quickly.
What size RES and SMB were you planning on stocking?