Just a warning, slow down!
I know we are all excited to get battling, but I think there is a lot we need to learn before we spend all that dust and candy. I have been monkeying around with different pokemon and the performance isn't always what you might expect. Some moves take much longer to charge. Also, on TSR they are talking about charge moves and that 1 bar moves may not be ideal because of the shield. Pokemon like Kyogre lose a lot of effectiveness if you can simply shield the charge move. Also, I hope the costs of adding a move is lowered, but we will just have to wait and see with that.
Answers
If you have 10M dust, yes please.
If you're like me sitting on 400k dust - this is great advice. It'd be a huge waste for me to invest all 400k dust right now on what I thought would be good if I found out two weeks later that they're actually not.
Kyogre and Mewtwo both feel strong, but that doesn't mean they're actually stronger than the competition.
1 bar moves will make great wrecking balls after you deplete your opponent's shields. I've read Groudon is slated to be an absolute last slot beast in Master League due to Mud Shot having an obscene energy gain.
To the guy yesterday asking about Mud Shot Poliwrath, you may want to give them a whirl.