I hear you! Definitely Pinterest for color ideas.
I quickly realized our guest bedroom/upstairs in general gets quite hot in the summer so the comforter I’ve had since living in Indiana is way too hot! My MIL has very neutral quilts on all her beds and I like how light weight they are and in the winter you can add a fuzzy layer under. I bought a quilt for upstairs from Marshalls, the furniture is a dark espresso, so I got a creamy beige and I’ll end up adding sage green shams.
As for the master, I went super simple, down insert and white linen duvet. And then I switch out the sham pillows based on the major holiday with these from Amazon. I have dark red for Christmas and orange for Halloween/Thanksgiving/Fall and my normal is sage green. And then I have a theme lumbar pillow.
Also not sure of your bed size, but we have a king and I was tired of buying sheets that had king size pillow cases but only having standard pillows so these were on 40% sale the other week and they don’t disappoint. My bed has a ton of pillows on it 🙃