I also might just get a RCA to 3.5mm jack for my laptop which will sit near it for Spotify.

Definitely do that, your computer is a super easy way to access all the music in the whole world!

Do buy a beefy, thicker 3.5mm to RCA cable if you can just because the amount of times one of the thin ones I have had started to break and got super touchy with how they had to be plugged in to the 3.5mm jack justtttt right to work and not make a horrible hum.. is too many. A thicker one isn’t much more expensive and will save you many headaches. It isn’t a sound quality thing, it’s that the cheap thin ones often just aren’t insulated thickly enough or they break from bending way too easy.