I am also not an ostomy expert and have not experienced valve problems. Since your valve is currently not leaking, I would be inclined to delay surgery. When it starts leaking again, you could try leaving a catheter hooked up to a leg bag 24/7. That should result in less external skin irritation than conventional ileostomy appliances. I do not know if there are any surgeons who could repair your valve without using more small intestine. A dietitian might be able to suggest foods that would enable you to gain some weight without making your leakage problem worse.