i hammock, so this is really just conjecture regarding parts of it. however i rely totally on a tarp for protection from wind and precip.
#1. most nights, i don't even need or want to use my tarp. i love the openness of it all. i love being able to see everything around me. i feel more connected w/ nature. i'd say at least 80% of all nights i sleep out my tarp stays in its stuff sack in my pack.
#2. #1 leads me to think that if i were sleeping on the ground i would want a separate bug shelter from my tarp, for those exact same reasons.
#3. as the weather heats up, typically the bugs get worse, so using my quilt as part of my bug defense is out for this guy.
#4. cuben has made it possible for me to have a huge tarp and not really pay much weight penalty b/t a minimum coverage tarp. really 2 ounces for a MUCH MUCH larger tarp. sometimes though i still carry a little tiny tarp.
#5. i only get out in the dead of winter (read mid jan/early feb) a few times, so the majority of my backpacking is 3 season. if the majority of mine was in the winter, i'd probably want my shelter and bug net integrated (yes, the bug net provides warmth - it can actually deaden the breeze quite a bit. which is why i chose tulle over noseeum for the mesh on my hammock bug net).
i hope maybe some of these points may help guide you into a best decision for you. i feel everyone sort of makes their own best decisions regarding this.
if i was ground sleeping i'd go with a tarp + some sort of bug bivy w/ bathtub floor. candidates for the tarp would be a 4 season tarp from zpacks, hammockgear, or a mid from MLD. even the hammock tarps from zpacks or hammockgear make fine ground tarps. my buddy had his hammock break on a trip this summer and his zpacks tarp to set up over himself on the ground. the flexibility to seal off the ends or 1 end or neither end is nice.
as far as the bug bivy goes i'd likely try to see if someone would DIY one for me. a guy like papa smurf or even just throwing up a post on here. there are many skilled and talented people here. i'd like to get a bathtub floor (larger than most 1 person bug bivies, so there's room for my pack and shoes and enough space that i'm not hitting the net) sewn in to a tulle netting with some sort of loop that attaches at the top. then i'd simply ask my tarp maker to sew a loop on the bottom of my cuben tarp (which i have done btw) so i could simply attach my bugnet via cord.
wow, that was a lot...