EOS RP picture style settings - what picture style do you use ?

I've been down this rabbit hole many times, and, let me say, I start with standard, and usually switch to either Landscape or Fine detail, and tweak those. I shoot RAW+S JPEG and do in-camera RAW conversion. Autumn hues and Portrait get some use too.

I find the LCD on the back of my R, is more color accurate than the monitor on my 2014 MBPR 15". Blasphemy, I know. But, you start seeing the subtle changes in-camera RAW editing when you switch on Adobe RGB and SRGB. I use SRGB for compatibility sake, even with my own machine which doesn't do Adobe RGB either. But, I toggle it to see what colors are impacted, and usually mimic those with a profile, or modified profile and then some artistic flare if desired. Less is more.

Bottom line. There is not goldilocks with these sorts of things. Very context specific so you need multiple profiles for multiple things. I've done actual picture profile creation, and it's worth noting that there are a couple "baselines"

Standard - Emphasizes with Canon's unique proprietary formula certain colors, which are probably based off AF or metering if I had to guess. Bumping saturation with this profile impacts those areas more, if that makes sense.

Neutral - just that. Flat. I avoid.

Faithful - Sometimes I use.

Landscape - Emphasizes Greens and blues, but also has a different contrast curve, not just contrast. Very important distinction.

Fine Detail - Another Canon proprietary. Sorta like Standard, except, minus the emphasis on context, but still gives punch. Reduced over sharpening. Also modifies contrast curves, which often I either use it for, or avoid because interestingly enough. Watch your highlights and you'll see what I mean.

Autumn Hues - Based off Landscape I believe, but emphasizes Reds and Oranges very subtly instead of Green and Blue.

Portrait - Pinks and Reds get emphasis. However, it often upsets the subtle balances of color, so I'll try it at times but in fact rarely use. When it works, it works though. When it works, it's usually portraits where it's head and shoulders or tighter, or, something I want to give more red/pink emphasis with, say red fruit. Go figure.

When all else fails, don't forget you can mess with a profile directly, standard with +1 saturation or Fine Detail also with +1 Saturation, or -1 Color tone, get use.

I've found it's very delicate. If you want to mimic the punch of older Canons, use Standard, then Fine detail (if the former fails) with -1 Color Tone and +0.5 Saturation (you can only do a 1/2 stop in DPP4, not in camera). I've found this too results in too much sway to do cart blanc, thus, I've given up the goldilocks approach and instead fine tune certain "special" shots, and leave everything else standard these days and go back to RAWs (like I have lately) if desired to tweak.