A lot of people are saying that the Rattle Weed should be nerfed lol. It's so easy to have the entire crew running them letting you basically ignore the threat of adds. This is a tough one to balance!
That's what we wanted to do back then!
What we found in testing and many many playthroughs is that players would often go into a new area, see the World Stone/Shard and decide "I'm going to go back to town and level up for this next area". Since the area level is locked when you first go in, this ended up making every zone and every area much easier. So instead, it now locks the zone at +1 to your level (which is a mere 10% diff with even gear, very very doable) and if you level up, it puts you even or well above. Quite often people would level up their gun(s) twice but leave armor, so they'd be above on dmg, lower on armor, or vice versa. In our testing, we found it didn't have a huuuge impact on the time to kill (10% up or down).