Sorry I've had a super busy couple of days and haven't had a chance to respond, but it's great that there's a lot of good discussion going on in here. I found some time recently to chat with the Balance team about the gameplay purpose of Stealth in our game and wanted to share what came out of that.
As the Balance team currently sees it, the purpose of Stealth is-
Defense/Escape - Stealth makes you more difficult to target, and can also make it easier to escape danger. Skillful escapes using Stealth are cool.
Positional Advantage - Stealth makes it easier to get into positions your enemy would normally not expect you to be in. Since your risk of getting caught out is relatively low, you're less restricted by enemy map control than other heroes.
Map Advantage - Stealth makes it hard for enemies to know where you are on the map, which forces them to play more cautiously because they never know when you might show up in their lane or jump them on a Merc camp. This gives your teammates an edge in terms of controlling the map.
It's worth noting that none of these things necessarily require being able to show up invisibly on top of someone and 100-0 them. However as many have pointed out in this thread, several of our current Stealth heroes rely on that playstyle to be effective.
We still haven't determined what kind of changes we might make, but one possibility is trying to push some of our more burst-dependent Stealth heroes into having a bit more of a utility focus. Shifting some of their power to things like misdirection, scouting, map control, etc could be one way to make them feel more fair to play against while keeping them interesting to play as.
It's been interesting reading all the comments & ideas in this thread so far, and I'll keep popping in periodically if I have anything useful to add. Thanks for sharing your thoughts! =)
（原文来源：NGA 作者： dotZ）