I would like to see a gaming publication that most resembles the early issues of Dragon.
1. Print rather than PDF.
2. Black printing on clean white paper, not strange colors on other strange colors.
3. Decent sized font for easy reading.
4. Crisp B&W line artwork interior, color cover optional.
As far as content goes, I would like to see articles about how to plan a dungeon, map a city, design a world. I get tired of someone doing these things for me and then publishing it because to me much of this is filler, and think that general articles helping people design their own materials are more useful overall.
If the magazine wants to pre-make materials, you might consider the idea of picking one campaign world and sticking with it. This can even be an original campaign setting unique to the publication. Think about Judges Guild from the 1970's and their "Wilderlands" campaign where each module or adventure had a specific place to occur in their world. They gave us a city-state, a haunted house, several villages, and more. All tied together into a single campaign, and most of it came as parts of their magazine subscription.
Giving player tips seems better than extra classes. Having DM tricks that can be used in a home-brew campaign would be useful. I guess I would like to see an emphasis on how to play rather than enless monster ecology type articles and the like that (to me) don't enhance the gaming experience at all.
Just my two cents.