a) maybe use some mayo? I don't see why it should be messy or any of your dorm-mate's business as long as you clean up after.
b) build up isn't only from cones. If your hair is fine, maybe the products you're using are too heavy for your hair (I'm not familiar with them unfortunately) or maybe a shampoo every 2 weeks is too infrequent.
c) If you're in between protein sensitivity and craving, maybe regular use of products with small amounts of protein would work best for you.

HTH
My hair is in the 4s, low in porosity, high in density and coarse.

Love: QB - all of it, Bobeam - shampoo bars, Darcy's Botanicals - Pumpkin Seed Conditioner, Coconut Cupuacu Pomade, KBN - Shealoe Leave-in, Oyin - Juices & Berries, Kinky Curly - Knot Today, Ayurvedic treatments, my Denman and the cloud of kinky goodness on my head that I get to play with!