Best tokens build? 1 of 4 (Boros) (Standard)

Comparing Boros-Selesnya-Naya tokens builds to see which build stands out as being the best. Looking first at Boros.

Why play Boros?

1) Legion Warboss.
this is a great way to trigger Divine Visitation.
applies pressure and constant source of tokens.
with an anthem effect it gets really nasty.
mentor is perfect for this deck.

2) Heroic Reinforcements.
the deck needs more anthem effects.
haste is a welcomed bonus to catch opponents off guard.

3) Siege-Gang Commander.
has great synergy with Divine Visitation.
we are playing 10 sources of Goblins, each provides multiple Goblins for Siege-Gang to sacrifice.

4) Goblin Instigator.
synergy with Siege-Gang
great when followed up by a Benalish Marshal.

5) Boros Challenger.
a fine card overall, just wish this was upgradeable.
can be a little hard to cast turn two at times.
mentor is a great ability for this deck.
3 toughness helps this survive some early turns trades.

Where does Boros struggle?

1) You are forced to play Gates.
*the set really needs an Aether Hub style land to make two colored decks more viable. Playing dual lands that come in tapped with no upside is just wrong in standard.

2) The 2cmc slot is very weak.
*Instigator and Boros Challenger are fine cards, however they feel a little underpowered in this midrange build. They would both be better suited to a low to the ground aggro deck.

3) Not a whole lot of protection for your creatures.
*without green, it is much harder to protect our creatures against removal.

Overall:

The deck hosts a very solid assortment of midgame threats.
There are multiple ways to trigger Divine Visitation on the turn it comes out.
The early game is underwhelming. A turn 2 Instigator is not much in the face of a Steel Leaf Champion.
tokens, as an archetype, is at the mercy of Goblin Chainwhirler. The entire playability of tokens hinges on how strong the mono-red decks turn out to be.