I ride with a cyclist who is legally blind. He has limited vision but gets along pretty well. Most people who meet him on group or charity rides have no idea. Your limited vision is going to be an issue in traffic. I'd take to the bicycle and MUPs for now. If you like longer distances and open countryside, look up rails to trails conversions. Some are paved, some aren't but all are devoid of steep grades (trains didn't climb hills very well) and sharp turns. Ideal for new riders or those with some physical limitations.