My youngest rode (and still will ride) any coaster she is tall enough for. She was the exact minimum height one year so we would get measured every time by every cm who saw her. At a local park, 40” was the minimum for the upside down coaster and 42” was the maximum for the kid rides. We had a worker so confused as she would ride this huge scary ride and then she’d jump on the kid ride and then back to the big one.
That being said, my oldest flat out refused to do any of the big rides. With her we made use of the rider swap. I was quite sad because she was tall enough but just not into it. I still haven’t been able to get her to ride the local coaster, though she will do everything at Disney now. For our trip next year, the plan is for my husband and my oldest to go on the marcline tour, while my youngest and I hit the mountains at rope drop.
So, which will your kid be- no clue. My oldest was completely fearless in every other aspect and yet the coasters were a firm no. Youngest is normally a timid little sweetie, terrified of everything but those coasters called to her.