Everyone today seems to regard a tent as [/i]de rigeur[i], but I backpacked regularly for well over a decade before I owned a tent for regular three season backpacking. I did have a surplus Army mountain tent (heavy!) for winter outings, but we regularly used tarps. My need for a tent grew in later years when often me and my partner desired (ahem!) some privacy. Six pounds was a small price to pay.
Pitching a tarp is not rocket science, and bad weather gives you plenty of incentive to do it right.
If you can sleep warm and comfortable at night, you will be fine. It helps if you don't have to deal with blisters. Most everything else falls under the heading of minor inconvenience.
In those days (the mid 5os, just before the emerging boomers made backpacking a much more popular activity), you could walk into an unlocked cabin in the Arizona mountains and use it. You cleaned up afterwards and left a nice pile of dry kindling next to the stove. I also obtained, somehow, a Forst Service master key, useful the whole country over in those days. It was probably the ultimate lightweight piece of hiking gear and it wasn't even titanium.