I've got some... limitations. But I've never heard any complaints about my game style. I only run D&D 3E/3.5 campaigns at the moment. I liked 2E alright, but it's really time to move on, and I just didn't like the feel of 4E, and I'm still too new to 5E to give DM'ing a worthy effort. I've never learned another system beyond D&D, and I'm content with that.
I tend to play rules heavy, by RAW (with the exemption of a couple of house rules), but I use those rules to their fullest extent, to create expansive open-world sandboxes, or tight, action packed dungeon divers, depending on the vibe of the group for which I'm designing a campaign. I tend to work within settings, like Greyhawk, Forgotten Realms, Eberron, or Dragonlance, because I love the richly developed maps, cultures, and background fluff, though I have been known to brew my own settings. I've never used a module, though I'm not opposed to modules, and I'm pretty flexible with builds, as long is it stays withing the confines of any published WoTC material from 3E or 3.5, which (I feel) is more than flexible enough.
My build knowledge is solid, but basic, because I usually just pull my monsters right out of the pages, and never attempt to optimize my NPCs or BBEGs (because it's not their show... it's the players' show). But my strength is in story design, fluff, and rules knowledge/adjudication. Plus, I never abandon my players. Life catches up to me sometimes. But I've updated posts from the hospital before... if nothing else but to say something to the effect of, "I'll post as soon as the doctors patch me up and the pain killers wear off so I can focus again." Mostly, I can be counted on to post at least once a day.