A few general remarks in the hope that they help:
Intel i7-10700K -
good choice [though the above suggested i9-10900k would be better].
32GB Corsair Vengeance RGB Pro 3200 -
It’s not just the 3200 rating that’s important here. I would recommend a low latency of
CL 14 if the budget will stretch that far.
Crucial P1 1TB M.2 NVME SSD -
Yes, an SSD really is de rigueur here.
EGVA GeForce RTX 3070 XC3 Ultra -
A fair choice between power and price. Though be prepared to upgrade should a future
DX12 implementation require it.
Cooler Master MWE Gold 650 80+ Gold Certified Fully Modular Power Supply -
Arguably, for the difference in cost and with the future in mind, a better choice here would be a minimum of 850 Watts
So I still need a motherboard -
Your choice of mobo [for a given spec] is a fairly personal thing! I have done a lot of research in this area resulting in a change in allegiance from Asus to Gigabyte [particularly the Master models] on the basis of their VRM spec’s if nothing else. I have never experienced throttling with these boards!
Monitor -
Again, a very personal choice, made more difficult by the shear plethora of models on offer. If however you want the best colour balance, then a good IPS panel is your best bet! And, with that 3070 GPU in
mind, I wouldn’t shoot for more than a 2K [2560 x 1440] native resolution.
Finally, your case -
Again, a very personal choice! Objectively I would only consider buying a case such that the
radiator for that Corsair H115i can be mounted horizontally in the top of the case for best cooling performance. I personally like a big case, preferably one I can properly get my head into.
Large cases, generally, are easier to fettle with and offer more choices re case fans to
achieve good throughput of air.
I hope this helps.
I love building computers! I hope you enjoy the process too.
Good luck.