Pump?
I'm doing my first hard line build too. Nearly complete. I've used 6 x 500mm so far, had to order 1 more due to waste and "experimenting"...
I'm using a paint stripping heat gun from Wickes, 2 heat settings works fine.
From my experience so far tight short runs are not easy. Tube heats up and deforms at the end so you are left with bending further out and trimming. I've been using a Dremmel to sand down the ends. I've got an RX360 up top and the distro ports at the top of the res are real close, though I'm using the Radikult distro not the EK one, ended up using 2 x 45s. Also found take plenty of time chamfering the ends, I'm sure I've damaged some O rings. Will need to wait for my last tube to test...
With the distro you will want 2 or 4 90s for graphics card and chipset block if you are using one.
For coolant I was thinking of Mahems X1, not decided on colour yet.