Adding 240 volt circuit. Am I doing this right? I'm adding a 240 volt circuit for a new appliance. New appliance is 20 amps 3500 watts. 22 ft from circuit breaker. Homedepot only had a 30 amp version of type of outlet i need (nema 6-30R). So I went with a 30 amp 2-pole breaker (square D and HOM like my other breakers) and nm-b 10-2 wire. Was going to use neutral as the second hot. Does all this sound good? Just want to make sure I'm not missing anything.

I have a weird setup where three switches in one box control three rows of bucket lights separately on the same ceiling. One wall over is another set of 3 switches controlling the same 3 rows! I'm hoping I can connect the existing wires in such a way that I don't need to add/remove wire and can drywall over the one redundant box as well as 2/3 of the main box and leave a nice single switch. If I post a photo of the setup, could anyone help guide me to connect wires in such a way that a single switch will control all 3 rows of lights? Essentially, the setup is what you would expect - hot wires, ground wires, neutral wires, and the running wires between switches.