I played in their PTS (Public Test Server) when it was available and I can safely say that the difference in the post-30 game is night and day between 1.3 and 1.4 patches. I will definitely go back to that game once the 1.4 patch is released, which will be on Tuesday, Oct 25.
After getting a character to level 30 and playing the end-game content for a long time, creating an alt (or 2 or 3) were a breath of fresh air. The NPCs were not bullet sponges, the guns feel powerful, the loot feel like upgrades and the dark zone feel less like a gank-fest. So I do think they had the pre-30 content almost nailed down perfect, it's the post-30 that needed major overhaul and I'm glad they listened to what's left of their player base and reworked it. It's not perfect but it's a good start in the right direction.
Off the top of my head, the major overhaul that I, personally, think are the best in the PTS are:
- The change to the loot drops in post-30. In 1.3, the only way to get high end and gear set drops were from dark zone and incursions. In 1.4, any mob can drop high end, even trash mobs in the world in general. In 1.3 Underground, usually after 1 run of Underground mission, I'd get 3-5 pieces of weapons and armor, in 1.4 I'd easily get double that.
- Removal of the weighted drops from incursions. In 1.3, certain gear sets are highly weighted to drop on certain incursions only (and dark zone). In 1.4 any gear set can drop from anywhere, they only put the weighting on certain gear set pieces (like chest piece, holster, gloves, backpack, etc) on the incursions.
- Time to kill and time to be killed adjustments. NPCs are not as bullet spongey as before
- World tiers and readjustment of Gear Score drops. Though this isn't something that would affect a long time player like myself since with my current gear, I'll already be at world tier 4 when the patch drops. But the adjustment to gear score drops is huge! Previously, in order to pass a challenging mission, you'll need a bunch of 268 gear score items, which will only drop in challenging missions. It's a catch 22, you need the items to run the content but the items you need will only drop in that content. They've adjusted that in 1.4
- Overhaul of the gear set bonuses. Not perfect but better.
- No need to go to the Dark Zone anymore if you're not into PvP, the "Light Zone" and Underground also drops the high end and gear set loot.
I'm sure I'm missing out on a LOT of changes still but those are the biggest things I saw during the PTS and I had fun playing it in the test server. For a solo, semi-casual, player like myself, the changes are a long time coming and I will be back once 1.4 patch goes live. Will this bring back a lot of players that have already left? I don't know but I think a lot of them will at least give it a shot, or probably have during the PTS.