Ok, so lets say 4-6 years have gone by.
Okay, in that case, 5e will look very much like a "4.5 edition". It would only be
called 5e because of the backlash caused by the 3.5 version of the game.
If, instead, we wait 8-9 years, I think the time would be right for a more significant revision of the game.
At that time, I'm inclined to think that it will again be right to go for a 'back to basics' version of the game, harkening back to 1e rather more than is currently the case, and once again emphasising the "back to the dungeon" meme. Also, I think it would probably be aimed right at the core base of D&D, and less at the newer players.
Now, your the D&D brand manager, 5th edition is put in your lap. Your goal is to bring all of these groups together
In all honesty, I think this would be folly. Rather, I'd be inclined to go for a broad middle ground that gets most of the 4e players and most of the remaining 3e/Pathfinder players. (I think this latter might well require a renewed dedication to an OGL-style license, as opposed to the more closed GSL, and may require Paizo being brought back on-side. This latter may simply be impossible if Pathfinder remains a success.)
How do you handle core mechanics, what do you change?
If by 'core mechanics', you mean "roll d20, add modifiers, beat DC", then nothing. If you instead mean the layout of feats, powers and such, then I'm not immediately sure. I'm not keen on the 4e paradigm, but it clearly works, and mostly works quite well.
What do you do with races? With classes?
What do you do with fighters, rogues, clerics and wizards?
In the core book, only Humans, Elves (inc Eladrin), Dwarves and Halflings are included. Likewise, only Cleric, Fighter, Rogue and Wizard are supported.
Very soon after the publication of the core rulebook would come an expansion detailing a further 4-6 races and 4-6 classes.
Do you handle everything as powers or make seperate melee and spellcaster abilities into two different categories? Do you do something else?
Rather than daily/encounter/at-will powers, I'd be inclined to switch to a mix of per-encounter and per-
adventure balancing. I'd probably also switch to a mana-based system, so that a Wizard that really needs to cast
Sleep twice in a day can do so.
However, I'm no game designer, so this model might fail utterly.
How do you handle...
Monsters?
Minions?
Much as in 4e. I like the design here.
Split the pool in 2. One half refreshes with a short rest. The other only refreshes after extensive recuperation (it's a per-adventure resource). Healing spells and effects mostly only apply to the per-encounter pool.
Second wind would remain largely as-in in 4e (might change to a move action). Similarly Cleric prayers that trigger the spending of surges. However, these would apply only to the per-encounter pool of hit points. Also, there would be no limit on the number of surges that could be spent in a day.
Encounters?
Skill Challenges?
As in 4e. I like the design here. Although I'd fix the math on Skill Challenges. And by 'fix the math' I don't mean apply the current or similar patch - I'd get someone to run the numbers in great detail to get the desired results. The concept behind Skill Challenges is genius. The implementation, not so much.
Bring back skill ranks, but allow only 1 rank per level (not lv + 3). Merge several skills to produce a shorter list of more general skills.
Split these into trinkets (what were potions, scrolls and wands) and 'real' items. Trinkets would be considered to be easily available. Other items would be hard to get, much more mysterious, and hard to identify. The game would be balanced on the assumption that PCs have few if any such items.
The DM's section of the core rulebook would advise DMs to generate custom items for their group, and provide extensive advice on how to generate such items. Example items would necessarily be few, but would quickly be expanded in a supplemental book of treasures.
All existing 'real' items would be retired (barring conversion guidelines).
Much as in 3e, but with the list cut down and simplified. I would advocate no more than 7 bonus types, for example. I don't like the 4e paradigm of 'feat bonus', 'power bonus', and so forth.
Prestige Classes or Paragon Paths?
As in 4e, or eliminated entirely. Classes should, however, be more customisable in general.
Class Powers or Talent Trees?
Talent Trees. Probably.
As in 4e, including the use of milestones, though I might call these something else.
Do you create a starter set? Do you keep the 3 core books? What material goes into the PHB?
One core rulebook, of no more than 250 pages. Text density can be a little higher than the 4e core rules, though. This needs to cover the core of the game, and do so in such a way that expansion is easy and doesn't require redefinition of game elements. This book will include 4 core races and 4 core classes, enough material for the first tier (actually, I'd bring back the BECM tiers, and cover the first two in the core rulebook, extending to level 14). The list of powers would necessarily be limited, as would the options for magic items and monsters.
The Starter Set would hit the stores at the same time as the core rulebook, and would in fact include the very same core rulebook, plus an assortment of PC and monster tokens (or minis), dungeon tiles, a book of sample adventures, dice, and whatever else seems useful. It would be much like the starter boxes for "Warhammer Fantasy Battles" or "Warhammer 40,000" in that respect. I'd probably re-do the Starter Set every year or two to try to draw in new blood, but the core rulebook would remain the same.
Very soon after the first books are out, I would issue the "Advanced Player's Handbook" (covering additional races and classes, lots more powers and other character options, and the rest of the level range), the "Advanced Dungeon Master's Guide" (lots of advice on running games, preparing games, and so on, plus sample traps, treasures, and various other things), and the "Bestiary" (the rest of the monsters). Possibly also the "Grimoire" (spells and other powers) and "Tome of Treasures" (magic items and such), depending on how much material was generated. However, each of these books would be mostly modular (albeit assuming the full level range is being used), and each would also be strictly optional.
How do you plan out and execute 5th edition D&D? How do you market it? What else do you do to build the D&D brand?
This depends very much on how the DI does. If it succeeds, it probably safeguards the future of the game indefinately. If it fails, or is a marginal success, then a different approach would be required. It's hard to imagine what that approach might be - in 8-9 years the FLGS might be a thing of the past, or they might have been saved by a new 'Magic' phenomenon.
In closing: there may be one or two good ideas here. I'm aware that there are also a whole bunch of really bad ideas in here, and I have no way of sorting them out. And I'm not sure how much of this is based on my opinions of 4e, about which I am more than a little sceptical. So, make of it what you will.
Also, isn't it rather early for a "how to do 5e" thread?
