Yeah I even dont like playing only 21 lands. IT seems too greedy.
Potential Humans:
Cartel Aristocrat
FireFist Striker
Frontline Medic
Gore-House Chainwalker
Rix-Maadi Guildmage
Sin Collector
Thrill-Kill
Young Pyromancer
Master of Diversion - dont laugh, this guy seems good
Other potentially good cards:
Tymaret - prevents exile on necromancer
Boros Reckoner - only 2 lands doesnt cast it, it might be good sb slot.
Assemble the legion - good splashed to SB wincon for mono black
Gift of orzhova - for agro deck
Glare of Heresy - sb card
Profit Loss - good vs most agro decks
Orzhov Charm - solid removal
Wear Tear
Also last Premier event 9th place:
4 Blood Crypt
10 Mountain
3 Mutavault
4 Rakdos Guildgate
3 Swamp
4 Chandra's Phoenix
3 Exava, Rakdos Blood Witch
3 Firedrinker Satyr
4 Firefist Striker
n1 Hellhole Flailer
4 Rakdos Cackler
4 Spike Jester
3 Stormbreath Dragon
2 Chandra, Pyromaster
2 Dreadbore
4 Lightning Strike
2 Ultimate Price
Sideboard
3 Dark Betrayal
3 Doom Blade
3 Mizzium Mortars
2 Peak Eruption
2 Skullcrack
2 Toil // Trouble
As we can see more agressive with more creatures version of our deck. Note no Pack Rats, but with more 1 drops. Also much less removal than we have.