Welcome to humanity. Personally, I like most of the changes, although some took a while to get used to. Things like towers not having ammo were overall good for the game, although people who played heroes like Zagara would likely disagree.
The old stealth was problematic because it wasn’t a level playing field. I have vision problems (I have worn glasses since the 6th grade and contacts for sports since I have an issue with astigmatism in my left eye that contacts can’t fully correct), could only reliably see stealth under certain conditions. On a bright map with a consistent background, like Sky Temple, I rarely missed a stealthy. On a dark map with a textured background, like Garden of Terror, I would pretty much never spot it. It wasn’t a l2p issue, it was a “you are physically unfit” issue. I did try changing my resolution and graphics settings, but to no avail. Towers of Doom, Garden of Terror, downstairs in Haunted Mines, all of those areas were places I simply could not see stealth.