I know I can't really "work" him until he's at least two or three years old, but can I just ask him to walk and turn/flex for 5 minutes or less maybe 2-3 times each week? I'm 21 and weigh a little less than 130 and my saddle (if I did get on him with a saddle but like I said he did fantastic bareback) is on the lighter side. Flash is very well built, wide, muscular, will be about 15.1 hands (though he still has about 8 inches to grow), and has excellent confirmation - his only flaw is that he's toed out a little in the back - maybe he will grow out of it? '
Just to give some perspective, he's my only horse so I'm not spending time working with other horses. My dad had me ride and break our other family horses between 18mo to two years old, but then again I was around 10-15 years old and 80-100lbs at the time. Flash is my baby and his health and safety are my first priority. Thanks!