I would either suggest a mirrorless camera or a small dslr with AF micro adjust (canon).
The beauty of mirrorless is that you'll seldom have back/front focus (sony/fuji) If you go micro 4/3 the newer bodies will have very good focus too (panasonic proprietary DFD or olympus hybrid phase detect/contrast detect AF).
I cannot ever buy a dslr with no micro adjust due to the chances of having a lens miss focus due to the tolerance of calibration of the camera body vs lens calibration.
I recently purchases a cheap Canon 50mm f/1.8 STM prime just as a throw around for my 80D. The shaprness at f/1.8 was very good with some AF micro adjusting and reasonably sharp as I moved away from the subject. Testing that same lens with my 5d3 and 5d2 that lens was not as sharp even when micro adjusting and the approximately 7 feet away the test subject was soft and a blur. I returned it happily!!!
With my fuji I've never ever experienced soft images. Extremely spoiled that every lens works perfectly with no focus issues !!!!
OP not sure in your area but if your going through the troubles of saving weight mirrorless is the way to go. If you just want a smaller dlsr I am extremely pleased with the IQ I am getting with my 80D. Slightly larger than a rebel series but the performance is incredible.
If your not using flash I'll have to say my fuji with 18-55 kit lens ($1000 range) would surpass the IQ of a high percentage of older gen canon crop sensors with $$$ lenses. I still feel the IQ from my 80D with 16-35 f/2.8mk2 is not as good as my fuji with kit lens!!!