I'm having a hard time believing Stockfish endgame technique sucks, what program are you running it in? Isn't there some way to improve it's "thinking" process by adjusting the depth of ply search, time spent on each move (or entire game) etc?
Try Houdini and Firebird, they're both free although I can't say if either one will work better for you.
I'm currently enjoying studying Silman's complete endgame course. I usually test myself against an engine (Stockfish) to see if I have learnt a particular endgame. The problem I'm having is that Stockfish plays lost (from the engine's perspective) or drawn endgames poorly. As you know, in many technical endgames there are certain tricks and traps to look out for such as stalemate possibilities etc, but Stockfish doesn't try to reach these position and trap me, and instead plays meaningless and harmless moves when it understands that the position is lost (or drawn) if I play accurately.
Is there an engine that better emulates a (strong) human player in these situations, that will try to set up these traps so that I can practise the methods for avoiding them?