Rendolf

The clown the farthest south and west in Agate Circus is another move relearner. The devs thought ahead when they locked you out of part of the game. Edit: It's not a clown and it's in the southeast, but it's still a move relearner.

The problem with that strategy is that in the Glitch Field, Dark moves do Normal damage. The only thing that Psychic is weak to here is Bug, since the field also makes them immune to Ghost. In that case, the only super effective move you could get with your current would be to reteach your Sandslash Fury Cutter. A strat you might be able to run with that would be to lead with something that has Snow Warning like a Vulpix or Snover or what have you in order to utilize Slush Rush. If that isn't enough then you might have to either try and brute force it or train up something that can take it down.

Ohh tbh I never actually realized that the Growlithe egg trade was one of the encounters determined at the start of the game, although I guess it makes sense. But dang that kind of ruins some of my plans with future runs.

Technically you can get more Exp. Shares by getting extremely lucky at the Lottery Corner, but that's not very likely. I would say to double check your bag and if any of your Pokemon are still holding it, otherwise you might've accidentally thrown it out.

Unless it's your starter, you don't get a Froakie until extremely late in the game, and Torchic is almost as far up there. Beldum isn't available until after you get the 13th badge and Goomy is after the 14th or 15th. You have a pretty low chance to get a Togepi fairly early in the game which you can try to SR for, otherwise you can only get it around the same time as Goomy, and Grubbin is available really earlygame but you have to wait until you get the 7th badge before you can fully evolve it. If you're fine with waiting that long to have your full team then you should definitely have fillers that you're comfortable with, you would be keeping them for a while. If not then you may want to rethink some of them, or just try and get what Pokemon you can as they're available.