Actually at this point trading fish is something I haven't even considered or concerned myself with... the total area of the three ponds I am digging is barely going to be 1/2 acre.
These are for livestock watering (horses and cattle), pasture irrigation and water control first, if it turns out well and everything looks like it will do those without a problem, stocking it would then be planned.
I hope I don't hit any buttons with anyone for saying this.. But I know that's no where big enough for LMB (so there would never be that type on intention) and if I do decided to stock anything in it down the road it would probably be exactly what he has in his pond which is Bluegill, Shellcracker and catfish.
I grew up and spent the first half of my life in eastern Iowa on a large farm, we had three ponds there (all my dad and grandpa built), Dad is coming down for a month during this process to run some of the equipment and help and make sure I get it right. But those were all very large ponds that we did stock for fishing as well as the above. I wish I could build these ponds bigger but the layout of the land and my long term plan values the grazing land first.