Let's start off with...
D&D Miniatures
I would retain the current release schedule of three sets per year. Additionally, I would ensure that every fourth set (counting from Harbinger) was a starter set, and every fourth set (counting from War of the Dragon Queen) was a huge set (if economically viable). I would push for the increase in the number of thematic creatures per set to about 35% while at the same time doing my best to limit the number of "weird" creatures that cannot proxy for anything else to a minimum (maximum of 2-3 per set).
Additionally, I would take measures to improve quality control and do my best to raise the level of paintjobs to what it was before War Drums. If necessary from a financial point of view, I would rather reduce the number of minis per booster by 1 or increase the number of creatures/rares per set (requiring people to spend more cash to complete a set) than further degrade the minis' sculpts and paintjobs.
Core races and monsters would receive a limited number of dedicated slots per set. This would ensure the following: A) newcomers to the game could always count on getting needed PC minis/monsters; B) old-time collectors wouldn't be swarmed with too many repeated figures. For instance, there would be three slots for humans, one for dwarves, and one for elves; a combined slot for gnomes and haflings; a slot for orcs, gnolls, and bugbears; a slot for reptilians (lizardfolk, troglodytes, etc.); and a slot for hobgoblins, goblins, and kobolds.
The Icons line would remain limited to two creatures per year, one released in early December (in time for the Christmas craze), and the other in late May. I would also offer repainted versions of the Icons minis at GenCon.
Monster books
Monster books apparently sell, so, despite my personal preferences, I wouldn't stop producing them. What I would do is try to strike a balance between creating new monsters and converting old favorites, as well as try to make the number of different monster types about even in any given monster book. So, no more 30 new humanoids and only 2 new fey. I would also push futher the idea of advanced monsters, perhaps including as many as 20 fully-statted advanced core monsters in every new monster book. And I would hire Blackdirge for this job. Oh, and every single monster would have at least one sentence about its suggested placement in Eberron and FR.
I would continue with the creature codex series (Draconomicon, LM, LoM, FC1, FC2), first publishing a third Fiendish Codex that would deal with yugoloths, rakshasas, night hags, gehreleths, and so on. Two such books per year seems about right.
Splatbooks
Splatbooks sell as well, although I am not convinced they sell enough to justify their current number. To avoid saturation, I would publish about two new regular splatbooks per year (160 pages), and one "mega-splatbook" (224 pages). I would revise the current PrC format and reduce the filler text to a reasonable amount, while keeping the crucial "fluff" parts. I would also ensure better "hyperlinking" of the splatbooks, with every PrC having a list of recommended feats, equipment, and so on. Finally, I think the PrCs could use a set of "alternative" prerequisites to avoid shoehorning all their members to look exactly the same (e.g. "either Iron Will or base Will bonus +4"). The mega-splatbook would be in the style of Unearthed Arcana and try to cover as many systems as possible ("the kitchen sink approach"). It would always include new warlock invocations, new incarnum stuff, new weapons of legacy, new psionics, and so on, and so forth.
Environment Series
The current trend seems fine.
Campaign Worlds
Despite my ambivalence towards Eberron as a consumer, I would push it really hard as a publisher. On the other hand, I would do my best to publish an equal amount of material for FR. Basically, for Eberron, i would go for 2 regional/organizational books, 1 splatbook, and 3 adventures every year. For FR, I would do 3 regional/organizational books, 1 splatbook, and 1 adventure per year. I would also absolutely refuse to publish a campaign book that was less than 192 pages in length.
Oh, and the first FR organizational book I would do would be a 320-page Faiths of Faerûn, combining the holy trinity of 2nd edition religious sourcebooks (F&A, P&P, DD). This book would include no deity stats whatsoever. Not even avatars.
Special Books
Twice per year, I would publish "special" books, covering topics not easily included in other books. These would include one-off campaign settings, mega-modules, and so on. One of the first would be a 288-page book on Sigil (PRE-FACTION WAR). This would be followed by a Castle Greyhawk sourcebook (i.e. a cunningly disguised Greyhawk campaign setting that even non-GH players would be inclined to buy).