Advice on building a PC.

Hey team, looking to slowly build a midrange gaming PC. My plan is to buy the mobo/cpu/ram, and install it in my current case, use my GPU (AMD 290) CPU, and storage and upgrade those as I get the cash so im not dropping it all at once. My question is if i target a stock ryzen 3600 (dont plan to OC), and a msi x570 gaming plus mobo, from my loose understanding, i should target ram @ddr4 3600hz CL16, unless i want to try and fool around with infinity fabric settings? I also thought i read 3733 was a taget for the ryzen CPUs, so i was wondering it the +50-100CAD price tage would be worth the jump to 3733? For the GPU down the road im looking to get either a 1660ti or a 2060, but i am probably looking at after xmas (or black friday deals). Anyway, what are your suggestions for the ram or setup im looking at? Would i need to OC to get better timings? Im not positive how ram+cpu work together. PS: For the extra 10% boost ill probably focus on RGB when i get a new case