I say this all the time and I hate to again, but the solution is Labyrinth Builder. Use paired with Dimension Gate to banish your wall to prevent man-eater bug and extoplasmer. You can almost use the exact same deck that can be used to farm Kaiba here without changing a thing.
True. Two swords would be a problem if he happens to equip them both to him, you can use Emperors Holiday (just like lvl 30 mokuba) or any spell removal to handle that.
Ecto was always my issue too. The only solution I had was going on defense with set monsters. But after Paradox, Dimension Gate ruins Ecto. Use with a strong defender or a beatstick and his monsters cant attack. Then handle ecto at your leisure or power heal through it.