Upgrade path: Rega RS1 vs. Vintage Floorstanders

Hi all, newbie to HIFI audio here. I was wondering if anyone had advice:

I have a Rega Brio-r, Rega RS-1 bookshelves, and Sony autoplay record player.

My old speakers are floorstanding Marantz SP800s, and they are nice and warm, but much less detailed and clear in the upper registers when compared to the RS-1s. I like the RS-1s, the bass is tight instead of boomy, but they are maybe lacking some bass presence overall.

I'm thinking the record player is my next upgrade (Rega RP1?) but I'm not sure whether to:
a) stick with the Marantz speakers and eventually get better quality floorstanders.
or b) keep the RS-1s for now, even though they are pricey for something I might replace in the future.

Also, what kind of improvement in quality can I expect to see with a new record player?

Any thoughts or advice would be much appreciated.