Question MSI B550 - Advice for a build

[Zampe]

I have currently a i3-4th gen with R7 240 as graphics card, so maybe i'm not that up to date with recent parts, that's why i'm asking for help
My objective is running on most games (cyberpunk, doom, R6, NMS, etc..) at high or ultra with stable 60fps but not something crazy like in 4k, doing some work con CAD or design software in general and "to be easily" upgradable.
Currently i have a XFX RX 6600 XT SWFT 210 and the build i have in mind is more or less like this:

Component	Selection
CPU	AMD Ryzen 5 5600X 3.7 GHz 6-Core Processor	$300
Motherboard	MSI B550-A PRO ATX AM4 Motherboard	$140
Memory	G.Skill Ripjaws V Series 16 GB (2 x 8 GB) DDR4-3200 CL16 Memory
Case	?
Power Supply	EVGA G1+ 650 W 80+ Gold Certified Fully Modular ATX Power Supply

Now, the question is...
I want to spend more or less $450 (flexible) on CPU and MOBO, i'm pretty solid about the 5600X, but i'm not 100% sure about the MOBO
I need to get a better MOBO and cheaper CPU, or is alright as it is? There are other MOBO way better than this one at about the same price (maybe getting a little past the $450 budget)? Some warning or tips i need to know about the MOBO?
I don't have problem about getting an Intel CPU and MOBO, if there are reasonable better choice instead of this one above
And for the last thing, i have not decided the case yet, if you have one or two you want to propose, i will be happy to see.
It's actually my first build, don't kill me

 

[Hellfire13]

Budget and location for the whole PC excluding GPU?
Looks good but can do better possibly.