Some useful information to help you sort your problems:
A. Swipe down to refresh breaks randomly due to a litho bug.
Workarounds:
1. If comments are disabled, enable them back again.
2. Try force-stopping the app and try again.
3. Downgrade back to v15.40.
4. Disabling general ad removal also fixes as reported by Reddit users.
5. Switch on comments location [alpha] from ads settings
6. Tap on any suggestions on top of the home tab and pull down to refresh will start to work.
B. Video quality preferences not working as per your expectations:
1. The feature "video quality preference" is implemented by Google itself and we have no part in that. If you want the old UI back, you have to ask Google for it.
2. For preferred video quality to work, you must update your vanced app to the latest version 16.16.38 using vanced manager's latest available version.
3. You can configure the manual video quality in vanced settings after updating and keep the stock video preferences as it is and it will start to work.
If the selected quality doesn't work, try clearing data and set it fresh.
NOTE: Vanced preferred quality is broken on portrait/vertical videos hence it won't work there.
C. Chromecast/casting is still broken on Non-Root due to microG bug:
It has to be patched on upstream microG or a suitable fix to be made by us. Please wait patiently until it resolves. Till then, use the stock YouTube app or root variant of Vanced.
D. Videos lagging after the update?
It's because of forced ExoPlayer v2 implementation by Google and unfortunately not every device can handle huge resources and unsupported devices starts to lag while streaming.
The best possible solution to this is to force VP9 codec from vanced settings > codec override or using the custom codec options which resolves it for you.
E. Unable to open links from description of YouTube video's?
You have to disable the official YouTube app from your device settings to be able to open links from description in Vanced.