So we've looked, separately, at some interesting elements I think make D&D "work": a solid baseline, an experience point system that rewards play beyond the realm of combat, and an achievable "end game". As most of folks reading this particular blog will already know, the gradual erosion of these elements over the later editions of the game led some to keep playing, or return to, the older editions, or produce retroclones or variant d20-based games like BasicFantasy RPG and C&C.
An interesting alternative to that mindset was proposed, back in 2007, called E6. What this did, in a nutshell, was to take the existing 3x rules and pull them in nice and close to the baseline - characters topped out at 6th level and gained only feats from then on. This had a neat effect on the assumed universe of an E6 campaign; everything was at a power level much closer to what we would think of as "normal" in a sword & sorcery setting - the scary monsters like dragons and giants stayed scary rather than becoming mere stepping stones to get at challenges of an ever increasing power level ("Epic!"). This approach holds a lot of appeal to me - it acknowledges the strengths of a later ruleset (which I think we in the old-school community are often too reticent to do) while finding a clever and effective way to reign in the obvious problems with that ruleset. It neatly recreates a more traditional rpg experience by having a period of dungeon crawling followed by a period in which more high-concept campaigning will come into play.
But, I would be remiss if I concentrated solely on rules when it comes to "what works in D&D". As the revolving door of editions spins increasingly faster, something extremely important tends to get forgotten. If you've been following the whirlwind of 5E newsbites, you've probably noticed some familiar names keep getting mentioned: "Keep on the Borderlands", "Lost Caverns of Tsojcanth", "Tomb of Horrors", and so on.
Yes, I'm talking about Adventures!
One of the biggest things that is simply missing, from late 2E on up, is memorable adventures - the kind that everyone you know who plays D&D has played, the kind that becomes a part of the whole gaming vernacular and a measuring stick to gauge other adventures by. Since WotC's acquisition of the brand, only three titles come to mind as having any lasting impact on the collective mind of the gaming community (Sunless Citadel, Red Hand of Doom, and Keep on the Shadowfells), which over a course of 10 years is a stunning failure. The best adventures have a way of making players not care a whit what ruleset they are using. Companies like Necromancer Games, Goodman Games, and Paizo were able to step into this gigantic hole left by the game's official publisher, and build a nice business around giving folks what they needed - great adventures. While many like to blame 4E's perceived failure on its rules, I tend to lay the blame equally on the fact that WotC didn't pursue an aggressive publishing schedule of consistently engaging adventures, and at the same time refused to add their new ruleset to the open license that enabled third parties to produce adventures to go along with it.
As 5E begins its open playtest (you can sign up for this here, btw) in a couple of months, I am hoping that the discussion of rules does not completely crowd out a discussion on what players will get to do with these rules - will there be a renewed emphasis on adventures?