so you got a phone that works for you but you still want to replace it because... idk, just 'cause.
you could spring for an used, ex-flasgship phone that was abandoned by its brand but still has lineageOS support. e.g. Poco F1 or Oneplus 6T fit that bill. I can get em locally in the $50-$100 region. that thing has a fast SDM845, 8 GB RAM, full LineageOS support and even postmarketOS, Mobian and Ubuntu touch support, you can swap the batteries, etc.
so for like 5% of your budget, you get a new toy to play with and test what life is like on the other side of the fence and possibly gradually ween yourself off the corpo spyware. so, if it scratches your itch for that kinda money, I'd call that frugal.