I'm short, but my barn doesn't have tall horses for lessons 😂 The tallest horse I rode was 16.2hh and my stirrups were super long so 🤷♀️ But I think you can't be too small! Just make sure he knows your up there!
As someone who is vertically challenged, I will say it is more difficult to control horses that are 18hh+ mainly because I cannot wrap my leg entirely around the horse. It is not impossible, but it can definitely be a challenge to control the horse and stay with them over fences.
well, you could be too small if you can't control the horse because it's too strong for you. if your 4'11, you wouldn't want to get on a 18 hh horse because firstly, it would look weird and most importantly, it would be harder to control it.