Im not expert. but heres my take. That "nice" buck had the same genes his first year, his second year and on and on. So by the time he's "nice" he's already contributed those "nice" genes to the gene pool. Could you wait for one more season....well yeah, buth then other "nice" buck might not get a chance to spread their "nice" genes as much.

Nature's a gonna take care of itself, if you've scouted a nice buck, and put the work into getting an opertunity to take him there is absolutely no reason to feel bad about.