Im pretty sure the only reason mono-red has nearly as many +1/+1 counter decks as blue and black is because of Ashling the Pilgrim, which is a funny deck, but not likely a great fit for the 99
One strange wrinkle for Birds is that it actually makes great use of valiant creatures, as many of your best cards like Plumecreed Mentor and Plumecreed Escort freely target your stuff
Each game does involve large decision trees
TPCI Releases Alternative Play Handbook: Raid Format, 2v2 Team Battles, & More
Candelabra of Tawnos can go wild if you get a land in play that produces multiple mana, and Candles of Leng will almost always draw you a card when you use the ability
Three more commanders join the ranks, Bello, Bard of the Brambles, Wolverine, Best There Is, and Slinza, the Spiked Stampede, each one exceptionally strong options to lead your deck