The bottom of your pedal is 5½" from the ground? Mine is only 3" inches from the ground and I pedal through 20 mph turns and never hit the ground.
So something is wrong. Not only is suspension suspect but crank Q factor and pedal width too. Are you using really wide platform pedals? When I test rode the model bike I now have they put really wide platform pedals on it and I did have some pedal strikes in turns while in the parking lot. But when I put my narrow SPD pedals on the bike it was no issue for turns.
Certainly increasing tire diameter will help, marginally, but if you get to changing actual wheel sizes, then you are getting into more money. Why not just look for a cheap used road bike?