25v 1000uf low esr capacitor for the base of the pigtail. The motor wires might not be long enough to reach esc, but usually 18awg or 20 awg are used.
Have you got mounting gear for the board like 3mm nuts & standoffs maybe vibration mounts.
Youtube is your friend as well as Google. There are tons of tutorials on building a quad. You will also get a grasp of the components you will need.
Unless you've got experience doing "fine point" soldering, I would stay away from "4 in 1" or "all in one" anything. And you'd be surprised at how much "tighter" things get on a 215mm frame.
A couple more thoughts. I don't think you really need 35A ESCs for those motors, but it does give you plenty of head room. I don't think that a 215mm frame is large enough to swing 5 inch props(mine wouldn't).
I would definitely recommend going to a 250mm frame. There's lots of them out there and they're fairly inexpensive, even the 100% carbon fiber frames............
Yeah I'm hoping it should be able to swing them.... think it it will. If not I'll shelf the frame for a future build.
Yeah going for 35A over 30A was purely for room to upgrade motors at a later point. As they are only like a fiver more than 30A seemed silly not too...
Other than that shouldn't need anything else? Not too worried about the soldering to be honest, do basic soldering at work reasonably often. A few days a month... so no expert but not totally pant either.