If you really love the Thunder Wave chains, it might be best to just learn the chains and always finish at the edge with HSB or fsmash in order to set up an edgeguard, since Pikachu's edgeguard game is very strong and it's still going to do nice damage. This sort of thing will also definitely KO the lighter characters, that is, I don't think you actually need the MQA lock to finish off some characters [it might be necessary for like Bowser or whatever, but Puff should just straight up die at the ledge at 70% to partially charged fsmash].
You could also attempt to finish the lock with uthrow thunder or usmash thunder at the ledge, since that will do more damage at the end of the lock and even if it doesn't KO, set up for an edgeguard.
I don't really think meteor QA is necessary, although I suspect when custom movesets are redone, we might replace one of the lesser sets with 2321 to make it an option for those who want to use the lock [if it's not out].