Uhm, no further comments, so I really understand the issue is within LE and I need to wait for LE11?
Yes, the "famous" deinterlacer in the LE10 and LE11.
Was added in the LE 11 nightly, to the ffmpeg, some kind of patch for better handling the deinterlace (the LE11 beta 10.95.0 don't have it, don't know if in the LE10 nightly was added or not). Make a backup (or better use another sd-card) and try the latest LE11 nightly, maybe you will see some improvement.
I'm using 3 RPi3's, one with LE 10.0.4, two with LE11 nightly. For FHD live TV streams (h264, tvheadend), in case of LE10, sometimes appears some green artefacts, only for milliseconds, at the bottom of pictures. With the LE11 nightly, instead of green artefacts, some pixelation appear sometimes, mostly when major changes in the picture. L11 nightly with HD ready display (720p, the third RPi3) works better. I still have some SD channels, with mpeg2, works always without issues (RPi3, no HW decoding for mpeg2).