Memory is Cheap -- don't make the application run slow by skimping on the RAM
[I assume you have a SLX install from the numbers]
I don't know what other people find, but SW support always seem to spend an inordinate amount of time poking at my SQL server until they are satisfied it's fast enough.
if you're doing a new install, then sure install the latest versions of everything all at once. Personally I like to make sure I've gotten NPM working first before moving on to the next thing. At least I'm only having to troubleshoot one issue at a time.