First, why are your videos in 480p30 when then original had been PAL 625/50? You need to capture into D1 frame, 720x576 @ 25i, then deinterlace into 50p. This will preserve temporal resolution and will get rid of combing.
To preserve 50p on Youtube, you need to upscale to at least 720 lines, that is, you would be upscaling into someting like 960x720p50.
If you are new to this, there are boxes that can convert into 720p50 for you in one go, but they will also add black pillars on the sides to hold the 4:3 picture in a 16:9 frame.
Second, verify that your levels and saturation are correct. The picture looks too saturated and too high-contrast to me, but need waveform and vectorscope to verify.
Third, judging by the channel ident, you need to shift chroma to the left a great deal.
Fourth, the video looks patchy, somewhat posterized, too coarse, not enough detail. Make sure you have enough bitrate.
Deinterlacing into 50p, correct levels and healthy bitrate should significantly improve what you have now.
This is how consumer-grade analog video can look:
https://www.youtube.com/watch?v=noLN3a10zCY Granted, it has been shot with a semi-pro high-band camcorder. Still, something to strive for
So far it is the best VHS/8mm video I've seen on Youtube.
I have recorded this with a PAL VHS camcorder (not SVHS), does not look as great as the video above, still at least the motion is preserved:
https://www.youtube.com/watch?v=pCQDaFFg3QM