You could pretty much copy and paste the Roger Moore era Dragon, but with modern game references, and I'd be happy.

In order of importance:
1. Light and stylish writing. Between the April fools issues, the often hilarious editorials, and quite a bit of tongue-in-cheek and just plain old fun writing even in the regular features, classic Dragon was written in a very entertaining manner. I don't want unclear mechanics - strong templating is very important for ease of use - but I want the flavor text and especially the comentary to be written with style and panache.
2. Personal take on the game by insiders - both at the design and development level (for this, the best model would be the current Magic the Gathering site) and at the personal, 'at my table' level (for which the best model is the Dragons of the classic years).
3. Content that brings other media (books and electronic games being the ones I care about, but I know others are more into the visual push media) into playable terms. This, I think, would be hard to do without Dragon's unique position; frankly, I don't know how they pulled of Silicon Sorcery/Novel Approach type articles. I would think licensing would be ruinous, but they must have worked out a sweet deal.
4. Development of existing mechanics. I'm not really interested in seeing, say, a new class. For a Wizards magazine, I want to see expansion of the warlock's powers, or new maneuvers for the ToB classes, or alternate class features for the hexblade (ideally starting with Mearls' fixed, non-sucking version of the class

). For an OGL magazine, I want to see new kit for coglayers (Dragonmech) and arcane mechaniks (Iron Kingdoms), not a new steampunk inventor class; I want to see a discussion of using the Thieves World magic system for d20 Modern, not a new d20 Modern magic system.
Now, a lot of my preferences would be format-dependent. For example, I would like new crunch in a fully searchable e-zine, whereas it's pretty much useless in a print magazine. I would be more interested in maps in a print magazine, where they could be released on a single high-quality glossy sheet of paper, than in an e-zine where they would have to be printed out and likely taped together.