Downgrade the gold and get CSP?

Looking to lower my annual fees. Current cards are Amex Gold/Platinum, SavorOne, and Chase freedom flex. Really want to keep my platinum, and my main focus is to get a good sign up bonus. Thinking of downgrading the gold and getting the chase sapphire preferred for the 100k bonus. 750 credit, 2.5 years of history, no issues with meeting minimum spend since I'm moving and need to buy things for the new apartment. However, I don't spend very much so I don't think the Gold 4x is that beneficial for me, vs. saving the annual fee and getting the preferred instead.