Sell it! Profit is profit, it is also tax free and Winter is approaching where the car would see less use and be sat outside in poor weather, potentially causing issues with the car.
Get it gone, sit on the money and bargain hard for the next car/deal.
SF90 - Don't do it, there are loads for sale and for good reason, the few people I know who have had privilege of driving one said though its mentally fast it is a very numb machine and more an experiment for Ferrari, there is a reason why values have dropped so much and will continue to drop, buying one of these will lose you 40-50k the moment you drive it out the showroom as trade is around 300k on them. Guys who have driven or owned an SF90 and driven the 296 GTB all say the same, the 296 is the better car and a lot more fun/engaging to drive and feels not really any slower, yours for 250-300k brand new depending on spec.
GT3 RS - If gen1 ONLY buy with a warranty, the engines have same issues as regular GT3 but there is no 10yr goodwill warranty, if buying gen2 RS remember they are quite a bit more harsher and values are dropping slowly on the gen2 car but gen1 values seem firm, even on the up, I personally feel they are not worth the 160-170k they are currently commanding, around 140-150k is a better buy. I can see gen2 cars back to around 180-185k over Winter, currently circa 200k down from the highs of 210-215k a few months ago for a lizard green none Weisach car, the latter is pointless by the way more a my E-peen is bigger than yours, the regular car is perfect for road and track. New GT3 won't hammer the prices as Porsche increased the base price of the GT3 to 136k plus options and rumours of another price increase coming, this if anything is why 991.1 GT3 prices have firmed up, gen2 GT3's have softened a little to around 140-150k they won't soften much more to be honest, your probably risking 10k, 20k at most and you just made 40k so your quids in, if the bubble don't burst you could even make more money.
812 - Excellent car, amazing car, feels a bit big on road but you drive an AV so no issue there, but the crazy bargain 230k cars seem all but gone, so the risk is will the current 260-270k cars drop back down towards 230k, that is the risk and no one really knows, Ferrari also have around 30k profit in the cars so the moment you buy, the buy back at trade is around 30k lower, remember that.
A well purchased Porsche GT car represents the least financial risk out of your options, they drive totally different to any other car, fit like a glove, take them anywhere and have the most comprehensive extended warranty of any brand, a safe buy I say, you should have bought mine.
Other options I'd suggest considering with low financial risk, BMW M2/M3, Porsche 981 GT4.
Like you I hate selling a car, I like to horde them but I am learning it is also good to jump in and out, try different things, especially as the days of ICE cars are potentially coming to an end, numbers and available cars on the market potentially reducing as people with similar mindsets buy them all up. If you can try cars without financial hit or minimal risk, I say do it, we only have one life so YOLO and enjoy.
What I will say the GT3 is one hell of a car, I literally will take mine anywhere never fear taking it down narrow B roads, easy to judge, not to big, great warranty and a very engaging and fun drive.