I can see why some players would think Boros, because that's where the rares are. But you don't have the Mentor creatures or aggro curve to make Boros aggro work. White really only has 2 playable creatures (Witnesses are acceptable filler only if you have many 2/x Mentors and need more 1s). Red only has 4 creatures total (plus a few more multicolor), and they're only filler-to-average playables. Boros is just not deep enough to make aggro work.
Boros midrange is usually just bad. If you're midrange, 3-4 colors is better and you don't want the same creatures that Boros aggro wants. Your pool has a ton of manafixing as well as Glaive of the Guildpact, so multicolor is where you want to be. GBu or GBwr or bURw maybe.
Curve:
1 - s
2 - cccccss
3 - ccccss
4 - cccss
5 - cc
6 - ccc
I'd be happy playing that. Although these colors don't have any rare creatures or spells, Affectionate Indrik and Citywatch Sphinx are basically bombs - high power level uncommon finishers. Add 2 Rhizome Lurchers and Watcher of the Mists, and that's a lot of ways to finish the game. In grindy mirrors you can also board into Molderhulk and/or Lotleth Giant for even more finishers. Not running Molderhulk or Giant main may be controversial, but Citywatch Sphinx is a better finisher and you don't want too many 6s and 7s game 1 in case you get paired against Boros aggro.
On the lower end of the curve, you've got some ramp/fixing, 2-for-1s, and removal to help get you there. You can adjust these slots as needed postboard to beat the opponent. Some of these are personal playstyle choices. Hired Poisoners are good if you need early defense or more answers to fat ground creatures. Pilfering Imp and Burglar Rats are good against control. Dissident is a good flexible slot, a 2/2 for 2 early or trading with a midrange threat lategame. Muse Drake and Hitchclaw Recluse slow down early flyers. You're a bit light on removal, but the Poisoners help with that.
16 lands because there are 2 mana rocks plus the Utopia. You could play 17, but I just had a single Island for the 17th land, so it didn't seem to make a big difference. You could also add Steam Vents as the 17th land, allowing a splash for Lava Coil and Risk Factor. I like having a high creature count in Golgari decks, so I didn't bother, but both those cards are strong and worth splashing for.
You could also splash white instead of blue, taking Conclave Cavalier and Ledev Champion. If you splash using Boros Guildgates, you could also run Lava Coil, Risk Factor and Response // Resurgence. Multicolor has a lot of payoff.
I'd have to build the deck properly myself before I can say for sure, but after examining the pool, I, too, would go for base Golgari with a splash of blue. Those sphinxes really are as good as rares. You'll have a lot of early game to stand against aggro, quite the number of removal spells, and the late game fatties for the longer games. I don't think, that splashing red into that for Lava Coil is worth messing with the mana, though, good as it is.
My first thought was some boros aggro, or boros midrange deck?
1 Candlelight Vigil
1 Citywide Bust
2 Hunted Witness
2 Loxodon Restorer
1 Parhelion Patrol
1 Righteous Blow
1 Skyline Scout
1 Sworn Companions
1 Take Heart
Blue (11)
2 Citywatch Sphinx
1 Dazzling Lights
1 Disdainful Stroke
1 Leapfrog
1 Maximize Altitude
1 Muse Drake
1 Unexplained Disappearance
1 Vedalken Mesmerist
1 Watcher in the Mist
1 Wishcoin Crab
Black (13)
2 Burglar Rat
1 Child of Night
1 Dead Weight
1 Douser of Lights
2 Hired Poisoner
1 Lotleth Giant
1 Mephitic Vapors
1 Pilfering Imp
1 Severed Strands
1 Spinal Centipede
1 Undercity Necrolisk
2 Direct Current
1 Fearless Halberdier
1 Goblin Locksmith
1 Lava Coil
1 Maniacal Rage
1 Maximize Velocity
1 Ornery Goblin
1 Risk Factor
1 Rubblebelt Boar
Green (11)
1 Affectionate Indrik
1 Arboretum Elemental
3 Devkarin Dissident
1 Grappling Sundew
1 Hitchclaw Recluse
1 Ironshell Beetle
1 Might of the Masses
1 Urban Utopia
1 Wild Ceratok
Multicolor (21)
1 Artful Takedown
2 Conclave Cavalier
1 Dimir Spybug
1 Erstwhile Trooper
1 Goblin Electromancer
1 Golgari Guildgate
1 Golgari Locket
1 Hammer Dropper
1 Ledev Champion
1 Molderhulk
2 Piston-Fist Cyclops
1 Response // Resurgence
2 Rhizome Lurcher
1 Skyknight Legionnaire
1 Truefire Captain
1 Undercity Uprising
1 Wee Dragonauts
1 Whisper Agent
1 Glaive of the Guildpact
1 Wand of Vertebrae
1 Dimir Locket
Lands (10)
1 Dimir Guildgate
3 Boros Guildgate
1 Izzet Guildgate
1 Steam Vents
1 Watery Grave
2 Gateway Plaza
1 Guildmages' Forum
Boros midrange is usually just bad. If you're midrange, 3-4 colors is better and you don't want the same creatures that Boros aggro wants. Your pool has a ton of manafixing as well as Glaive of the Guildpact, so multicolor is where you want to be. GBu or GBwr or bURw maybe.
2 Burglar Rat
2 Devkarin Dissident
1 Child of Night
1 Spinal Centipede
1 Whisper Agent
1 Hitchclaw Recluse
1 Erstwhile Trooper
2 Rhizome Lurcher
1 Wild Ceratok
1 Watcher in the Mist
1 Douser of Lights
1 Affectionate Indrik
2 Citywatch Sphinx
1 Dead Weight
1 Severed Strands
1 Urban Utopia
1 Dimir Locket
1 Golgari Locket
1 Artful Takedown
1 Undercity Uprising
//Lands: 16
1 Watery Grave
1 Dimir Guildgate
1 Golgari Guildgate
2 Gateway Plaza
1 Guildmage's Forum
6 Forest
4 Swamp
1 Lotleth Giant
1 Molderhulk
1 Pilfering Imp
1 Mephitic Vapors
2 Hired Poisoner
1 Disdainful Stroke
1 Muse Drake
Curve:
1 - s
2 - cccccss
3 - ccccss
4 - cccss
5 - cc
6 - ccc
I'd be happy playing that. Although these colors don't have any rare creatures or spells, Affectionate Indrik and Citywatch Sphinx are basically bombs - high power level uncommon finishers. Add 2 Rhizome Lurchers and Watcher of the Mists, and that's a lot of ways to finish the game. In grindy mirrors you can also board into Molderhulk and/or Lotleth Giant for even more finishers. Not running Molderhulk or Giant main may be controversial, but Citywatch Sphinx is a better finisher and you don't want too many 6s and 7s game 1 in case you get paired against Boros aggro.
On the lower end of the curve, you've got some ramp/fixing, 2-for-1s, and removal to help get you there. You can adjust these slots as needed postboard to beat the opponent. Some of these are personal playstyle choices. Hired Poisoners are good if you need early defense or more answers to fat ground creatures. Pilfering Imp and Burglar Rats are good against control. Dissident is a good flexible slot, a 2/2 for 2 early or trading with a midrange threat lategame. Muse Drake and Hitchclaw Recluse slow down early flyers. You're a bit light on removal, but the Poisoners help with that.
16 lands because there are 2 mana rocks plus the Utopia. You could play 17, but I just had a single Island for the 17th land, so it didn't seem to make a big difference. You could also add Steam Vents as the 17th land, allowing a splash for Lava Coil and Risk Factor. I like having a high creature count in Golgari decks, so I didn't bother, but both those cards are strong and worth splashing for.
You could also splash white instead of blue, taking Conclave Cavalier and Ledev Champion. If you splash using Boros Guildgates, you could also run Lava Coil, Risk Factor and Response // Resurgence. Multicolor has a lot of payoff.
Former Rules Advisor
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(The Gamers: Dorkness Rising)
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