Closed Beta weekend was a Barb, got to 20.
Open Beta was a Werewolf Druid, got to 25.
I played the campaign in full for Beta on the druid, did the world Boss, and farmed dungeons for gear.
Overall, I enjoyed my experience during closed Beta more. It was not because of the legendary drops increase during the time.
Instead, the lag spikes/crashes during open beta severely impacted my experience and enjoyment playing the game. I did not experience this during Closed Beta, and imagine because there was such a larger influx of people playing that it would affect the gameplay experience. However, while I was in town, there was little-to-no lag.
Once I stepped outside ANY town, and get close to ANY mobs, my PC was about ready to crash trying to load (5-10 seconds of not being able to do anything) and being thrown into playing reactively popping health potions scrambling not to die is a really, really unfun experience. There were times in the middle of dungeons where this would happen, and it just completely killed the experience to the point where I was ready to just alt+F4 and stop playing.
I bring this up not to whine, but to address a serious issue myself and others have experienced, that cannot be a normal experience when the game is live. This will be a severe issue for HC players if it’s common-place at launch.
Aside from this, honest feedback from playing primarily the fury Druid was that it was a fun experience at times, but overall, it felt quite underpowered. I did notice a pretty large jump in my DPS once I hit 25 and get some legendaries with good aspects and rerolled/upgraded some gear, I was doing quite well (1k crits on melee hits). But leading up to it was quite slow/difficult compared to others playing Necro/Rogue/Sorc.
Given that I played primarily a Fury Druid in Diablo 2 (all the way to 99 in Hell cows back in 1.09), I was anticipating this being the case, as Druids were arguably the most gear-dependent class for melee, but became powerhouses with the right gear. I imagine this will be the case for Druids end-game in Diablo 4 as well, but some small overall tweaks to damage and spirit gains for basic skills would make the lower-leveling experience stronger.