Sleeping under a tarp in bug season can be a problem. I don't think there is a large difference between a quilt or bag...mostly in warmer weather, I use my bag as a quilt anyway. Colder conditions means there are no bugs.
Anyway, I often use a tarp through the ADK's. Bugs are always a problem except for winter. I use a layered approach.
1) Your tarp will help with some bugs.
2) Your quilt will help with some bugs.
3) Permethrin on your outside clothing. You should keep one set of LIGHT long johns treated, too. Use these for warm evenings with lot's of bugs.
4) Keep a fire about 10' away from you. Some bugs like the IR. Some like the CO2. Give them an alternate target.
5) Smoke a cigar (more for waking hours.) Bugs do not like the smoke, generally.
6) DEET over all exposed skin. Most bugs will obey it. Not really recommended, but...
7) Wear extra-long sleeves. Close these up for the night with a hair tie.
8) Use the sleeping "net".
9) Someone suggested I use mosquito coils. It does seem to help but they don't last a long time. 3-4 hours is about it.
10) Cotton balls in the ears will quite most buzzing.
11) DEET on your hat, heavily saturated, will deter them from your head and ears.
12) Afterbite (oil & ammonia) will handle most bites.
Last week I was out in the ADK's in blackfly season. I didn't get one bite. Mosquitoes were also out. These can bite right through clothing. Avoid the areas that has a lot of mosquitoes, if possible. Using these techniquies, can keep you relativly bug free, but, do not expect to avoid all bites.
I have not tried to use permethrin on my down stuff, but, next week I will give this a try. I need to permethrin some new pants and a shirt, anyway. It is not really a repellant, but, even bugs will avoid something that will kill them. If you have a nylon, felt or wool hat, permethrin that, too. Permethrin will not stick to PET-recycled clothing too well nor many synthetics (example: polypropylene doesn't absorb much, it resists most chemicals.)