I'm not familiar with the Heroes 3 videos (how they should look in HQ), but I think the game is still playing low quality RoE videos, because they are more choppy than AB and SoE (at least these ones available at the starting campaigns' 1st missions).

About missing AB intro - I think this video will never be included, because someone said it was made for the earlier script with the Forge town.

I see. Indeed, when I started downloading the file, it had 2.0.0.16 in the executable name. You might want to show the version of the installer on a game page to avoid the confusion (it still shows 2.0.0, see the attached screenshot).

There are few more bugs in Heroes 3 and Chronicles, which appears to be not fixed.

1. In Chronicles, few cutscenes appears to be pixelated.
2. Artifact transfer between scenarios in RoE campaigns - there is an older thread about this. Is it fixed? If not, then maybe it could be fixed by taking the fixed campaigns from vanilla H3 (SoD broke this) and inserting it into H3 Complete?
3. Armorer ability bug - appears to be not fixed, but I think it can be fixed by editing Heroes3.exe with a hex editor. If hero has the armorer ability during castle siege, it should decrease damage from turrets, but according to Heroes Community forums, it increases it instead.

Here is the fix:
1. Backup Heroes3.exe just in case something goes wrong.
2. Open the file with a hex editor.
3. Go to value 1E220 and change the first 7D to 4D
4. Go to value 1E360 and change 7D to 4D
5. Go to value 65D64 and change 7D to 4D
6. Save the file. The armorer bug should be fixed.

I think this bug is also present in Heroes Chronicles, but I don't know how to fix it due to different values inside the files.