i have castile soap, though the current bottle is peppermint scented. it helps in the sense that if i can still smell it i haven't rinsed quite enough, though unscented would probably be better. for zippers wash, dry, then lubricate; i've seen everything recommended from high end stuff to candle wax and lip balm.
tbh outside of my clothes and groundsheet my gear hasn't gotten that dirty, though i just washed my quilt after thousands of miles. i was nervous i would screw it up lol.
Yeah, washing the quilt is something I'm nervous about. A big reason why I'm adamant about sleep layers.
I noticed how rough the tent zippers felt last trip and decided it was time for a bath. Lubing was definitely in the plan. I might spring for the zipper lube with the brush. Seems like it'll go a lot quicker that way.
I've never found the need for dedicated sleep layers, if it's cold i'll layer on my windpants and fleece.
sounds reasonable re: zipper care, zippers are always the first thing to go; i've tried to minimize them in my kit but haven't eliminated them yet, still have 2 left.