The build up of mucous could possibly indicate an oral infection of some sort. This may also explain the eye problems. When you open her mouth, is there any stringy/thick mucous? Are her nostrils clear and free of mucous or an abnormal amount of dry crust (its normal to have a little)? If it doesn't appear to be too bad, I would rinse the gums with an antibacterial solution - chlorehexadine being my choice for those type of things. Don't let her drink it, just rinse. If its persistant, a vet visit
would probably be in order. If she's eating well, it doesn't seem real likely though. Mouth infections are far from comfortable and usually the first symptom is going off of feed. Perhaps she just had a touch of MBD which slightly deformed her jaw, so her gums are always slightly exposed causing the mucous membranes to work a little overtime? Hard to say.
Frequent soakings/mistings can help with retained sheds. Vitamin E oil works well on areas of skin that are damaged, like burns. Other than that, its a sensitive area, you don't really want to pick at it or anything. I'd wait until her next shed and see what happens, as long as it wasn't causing her too much immediate discomfort.