I'm 5'7" and about 112lbs (I'm a scrawny little thing..) and Abby is 15.2hh and around 1200lbs. Probably the largest I will ever willingly go. I prefer 14.2-15.2. Short and stocky, speedy and agile. The long and lithe horses are very pretty, but not for me. I also ride western.
My friend's TB and a Swedish WB at my barn are both 17.2hh. Uh..no thanks. I'mma fall off and die.