Out of those 2 CPU fans, I prefer the Arctic Liquid Freezer II 360. They have good reviews and I've used Arctic products in the past on previous builds. I'm not familiar with EKWB.
I've been using Seasonic PSU and really like their build quality. Based on reviews, that specific model is really...
If there's a need, upgrade it. When you do upgrade it, do it towards the end of 2021 so you can get some decent discount and a good run with your 10700k. Unless everything you are doing right now are being capped, I don't see the need to rush.
Get a Z490 board now. Where you should wait is on the GPU. Unsure how much you're going to pay for your 2080ti but hopefully it won't be retail. Buy a 3000 series or 4000 series (if you can wait that long).
Yah, could be but there's a huge gap of loss opportunity between the $699 3080 and the $1499 3090. Now that AMD actually have a GPU tech that competes, AMD can run around freely between $700 and $1498 (as long as it performs at that price point) if NVIDIA doesn't counter. It's all good for us...
XBOX Series S has been available on Best Buy for the longest time if anyone is looking.