When you're as godly of a mapmaker that you are now, I think we can overlook your melee shortcomings and take into account how much you've already contributed to battle.net with your excellent, and seemingly flawless UMS games.
I myself have never been one to be considered great. During the time of my Clan DoS_, I was a decent gamer, able to take on probably a good 35% of the people I played in public games, though that's not saying much considering how many unskilled people like me there are out there now too.
Back in my heyday, I a decent Zerg player, but more often used Protoss or Terran. However on the rare occasions I did use Zerg, and not actually suck, I never found a need for two or more Spires. More on the basis that I found Hydralisks, Overlords (to drop with), and Scourges enough of a distraction to break a defense. With Lings and Defilers added in to help in the fray of anti-air defense.
In fact, I believe I held off a 12-14 BattleCruiser assault on my base with 2 Defilers, DarkSwarm and Consume, and about 18 Hydras. I'm pretty sure it was on Dire Straights after all resources had been consumed, and 3 of the 5 players had already been eliminated, and Allied/Allied Vision to watch the rest (it was all friends).
Considering I was never one to like the weakness of Zerg Air, and not happy with the slow ROF for Devourers, I've never had the need to upgrade more than one thing at a time.
Lastly, while I can't deny the power of Guardians, I find they're always far too unprotected on island maps while traversing over water.
