>>106399166
>>recommended case
>>no North
North & Epoch has a worse case frame; the Meshify 3 has a newly-tooled one (less front airflow obstruction).
North & Epoch's top panel radiator size is limited to 240mm; Meshify 3 can fit a 280mm rad at the top.
North includes mediocre Aspect fans (2x 140mm). Epoch includes 3x 120mm Momentum, Meshify 3 has 3x 140mm Momentum fans.
Fractal Momentum fans are very good; they can almost match the new Noctua G2 fans' overall performance.

Buy North if you like the design, but it's not a case worth recommending over the Meshify 3.

>>106357676
Depends on how loud you plan to run the AIO.

>>106350422
280mm AIOs are fine if you prioritize low operating noise.

>>106153340
Bigger is better, but it's not going to be a massive temperature difference compared to a 360mm rad (sub 5°C @ 180W for 13900K).
280mm or bigger is fine, you're probably not cooling an i9.
https://www.youtube.com/watch?v=VDB3ZBHh5Rk