Gil's "lack of spiciness," for the lack of a better word, makes more sense once you play his episode. His touchiness and impulse to mess with Walter doesn't only come from his urges, but also out of care for Walter. He's the one who mainly helped Walter out of his reclusive shell during high school, and it was Walter's request for Gil to be less uptight and be "more like his dad" (And we can see how touchy Edgar is). He's naturally a romantic person who values meaningful connections and would do anything to protect his special one, even if it meant hurting himself.
Though I will agree on Walter's hesitance being a bit worrisome. I believe Gil's route is specifically written this way in order to slowly build up towards a crucial moment, especially since his story about the Moon Goddess has already paralleled with his Day 10-12 (And soon 13-14).