I think you're doing more than enough too! The only thing I would do if I was to leave the kids and hubby for a few days is make sure the emergency numbers are listed clearly on the fridge (including pediatrician, dentist, your friends number, etc.), give him the medical insurance cards, laundry, and buy some frozen lasagnas and/or pizzas and plenty of easy snacks. Theres nothing wrong with your daughters eating fast food a few times or wearing mismatched clothes for a few days.
My husband has the kids one day a week while I work, and I love coming home to our 3 year old wearing a blue cinderella shirt, with pink floral pants and (if I'm lucky!) her hair up in a sloppy pony tail lol. Our 7 year old dresses himself, but i 'approve' what he wears before we leave the house. My husband took him out last week in camouflage shorts and a bright orange t shirt with a lion on it lol. Although I'm sure my husband would wear something similar if I approved ;)
The important thing is they all have fun and be safe while your gone. Your husband seems like a great guy to stay with the kiddos while you have a mini vacation! Show that you trust him and let him parent. have a fun trip and relax!