Silverstone. I know it has massive heritage and nostalgia but it always seemed like a flat, boring, uninspired track to me, so I never really got into it. For contrast, the tracks I find inspired and fun to drive are like the Nords, Mosport, and Bathurst.
That is until I found a need to deep dive into GTR2 FFB tuning and I started picking tracks to focus on to run lap after lap doing fine adjustments to FFB. Doing that I started to really appreciate Hockenheim, Imola, and similar tracks. Then I decided to try out Silverstone and, at first I didn't like it, but lap after lap I began to appreciate its turns and angles, its slight rises and falls, it's dips-into-turns, and its technical turns that at first turned me off but, having a need to do lap after lap at high speed, I began to appreciate their design and flow and the skill and focus needed to take those corners fast.
My advice: When you're bored sometime, force yourself to drive 20 laps on a track you think you don't like. I bet by the end of it you'll at worst begin to start appreciating the layout and, maybe, you'll even start to like the track.
Bonus Track: Sebring. Also assumed this was a boring, uninspired flat track...but actually driving it is great.