Tony Vargas
Legend
They were called martial damage dice (MDDs), at the time. Since 2e, 3.x, & 4e had all demonstrated more than amply that multiple attacks are problematic in D&D's hit-point/focus-fire paradigm, Next initially had everyone making 1 attack per round, fighters were given an increasingly large stack of dice to add to their damage to make them 'best at fighting,' in theory, you could trade dice for maneuvers, so if you wanted to do something interesting, you did less damage.I wasn't in the Forgotten Realms of Gaming when the D&D Next playtest was zooming around.
Is there something that was in the playtest you liked and it got cut? What was it?
I heard that all fighters orginially used superiority dice, which sounds interesting. How did that work, and how did the subclasses work?
The sub-system went the way of many proposed to help out the fighter over the years: it started with the fighter getting them, then other classes that 'should be able to fight too,' then, since it's a 'mundane ability,' finally everyone - then it was scrapped.
5e went back to the problematic mechanic of multiple attacks, so the fighter is a DPR champ, but not good for much else. Very 2e.
MDD's would likely have ended up making the fighter more like it was in 3.x - able, in theory, to pull some neat tricks in combat, but, ultimately, not using them much because the focus fire tactics demanded by D&D's hit point system make moar damage the thing to do.
CS dice are clearly a descendant of MDDs. They avoid the problem of fighter mechanics being eventually given to everyone, by being silo'd in a single fighter sub-class, so not even all fighter's get them, and avoided the issue of damage always being better by having them add damage when used for a maneuver instead of giving it up. That, in turn, required they be limited-use (short rest) where MDDs had been at-will, and the maneuver system ended up pretty limited and blah, with just a few top-tier maneuvers and nothing much of interest once you've learned them.
MDDs had potential relative to CS dice, and avoided making any class dependent on multiple attacks for effectiveness, so I guess I miss them a bit.
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I also missed the Sorcerer attempt, it was noticeably different from the wizard in a more dramatic way than the 5e incarnation. One of my playtesters didn't even try 5e when he discovered the Sorcerer he had enjoyed had been cut - he's playing 13A.
I also liked the idea of not tying skills to a particular attribute, in the Storyteller style - so as a DM you wouldn't call for a skill, you'd call for skill + attribute "Roll INT + Athletics to recall the rules of hurley."

I can't recall, ATM, when neo-Vancian kicked in, if it was from the very start or not. But I can't say I'm delighted with it.
There was a ranger in at least one packet - someone played one when I ran the 'crystal shard' adventure, I think it was. They were very good at tracking and pretty good in combat, as I recall.