Well I assume your BF% numbers are pretty inaccurate anyway. So stop obsessing about a particular percentage you want to get to. I suggest instead get a mental imagine you want to strive for and work towards that. Stop trying to put a number on it. You will fuck yourself over if you do. Just relax, and eat less food in general and move more, and you'll be fine in time.
So your goal is to lose fat, but long term why are you lifting? I mean are you leaning more towards "bodybuilding/looking good naked" or "powerlifting/being strong as fuck"? Because unless you are going to compete in powerlifting, strongman, O-Lifting or something like that, you can just drop the deadlift if you are having problems with the lift. There are plenty of other lifts you can do for back thickness and hammies.
Seeing as you've only been lifting 6 months, I would say you are just weak, should keep the lift and keep trying to use up linear progression for as long as you possibly can.
Your back rounds because you are still a newb and weak. This will correct itself as you grow and get stronger by consistently going to the gym and kicking ass.