ZOS, I have to say, you got it right! By scaling trials and introducing veteran and hard modes, you balanced the difficult right as it should be. I can run any trial and dungeon in normal mode with my roleplaying guild and have everyone have fun even if they are new, casuals or don't care about their builds. On veteran mode there is challenge enough to progress with a grope of average players. Finally, hard mode suits the maniacs who are crazy and invested in PVE. The fact you put rewards to drop on all modes, even with diminished returns, will help those that can't access the hardest version of the content, either because they aren't geared or because they didn't find a hardcore guild. You have introduced three difficulties in the game in a very subtle way, I like that.
Now, after caressing your head I will slap your buttocks. I understand that the new trend is sell new Veteran Dungeons, let's be honest here, since WGT and ICP its the same dungeon with mechanics disabled or enabled based on the difficult. VCOA was the last veteran dungeon introduced in base game patch and that was 2014! I believe you should definately finish all veteran dungeons on base game. Now, I understand that won't bring you profit because it is base game and it is time consuming to have a whole new area in those dungeons. So, how about you offer access to these old-new veteran dungeons to ESO+? Or make us buy a dungeon pack, maybe 5,000 Crowns. So we can get veteran Vaults of Madness plus all the other dungeons.
I have ESO+ and I talked with several friends, they would pay for the pack. I believe that would enrich the end game PVE and bring closure to all those dungeons that begged a sequel. Please, think with love!