It's great that ESO is seeking to incorporate more and more elements from previous TES games, such as the Justice system, which, hopefully, will provide a foundation for Thieves Guild and Dark Brotherhood. I think if Zos is going down this much anticipated and much beloved path, they should really bolster up the stealth system in ESO. I'm glad they included stealth from the get-go, but it often seems like it was tacked on to keep faith with the elder scrolls tradition. You can do stealth, but you're not quite sure of the benefits.
I fired up Skyrim today to take a look back at the stealth skill line that was in place for that game. It was an abundance of riches for people who like that style of play. You could pour points into that celestial skill line and acquire such benefits as backstab, muffled movement, deadly aim, assassin's blade, and the pinnacle was shadow warrior. I believe for the justice system to be successful, Zos really needs to have an ability system (primarily passives) in place that will offer these skills to all of the aspiring bad-asses out there.
You're probably thinking, well that's what the nightblades are for, but I think all of the classes should have passives that they could put skill points into that would encourage stealth playing. This type of approach would also promote the more deliberate, slower paced exploration of dungeons and delves. How many of us have complained that we do stealth in dangerous situations only to have other players rush past us inciting the mobs and alerting them to our presence. If stealth was a viable skill line that one could gain experience from and improve performance in justice system, I think you'd have a lot more players using it.