What is the price range for your GPU ? For me, I'd get the RTX 4060 Ti.
Likely to be released in late 2024 to early 2025.
I'm using the Lian Li Galahad 360 and it keeps my chip ice cold even when pushing an all-core overclock. Idle temps in the 20s and never goes above 70...
The newly announced G.Skill Trident Z5 royal should be the best choice.
ROG Ally X can support UHS-II MicroSD cards, so you'd better get some UHS-II microSD cards: