As someone who has yet to take a side on the whole "Big Zoo" debate, I have a few thoughts:
I am intrigued by the direction because I think Kird Ape, Loam Lion, and Steppe Lynx are all a bit underwhelming. Lynx is too swingy (it's better in speed zoo and burn), and the 2/3s just don't have the same impact they used to. Figure of Destiny is nice but realistically cannot be played as more than a 2-of. Until we get another 3/3 for 1, Hierarch could be the next best 1 drop.
On the other hand, the mana and exalted from Noble Hierarch is always pretty useful. Being able to play 4 Knights of Reliquary and a couple bombs like Elspeth and/or Jitte is fantastic in the mirror and against other aggro. They also make the deck more resilient to Wasteland/Stifle, which you have to expect.
Altering the burn/removal package too much is a poor idea, however. 4 Bolt/3-4 Chain/4 Path is solid and shouldn't change. Swords are not wanted here since the purpose of Path is to get rid of things burn can't remove (e.g. fat green creatures, Tombstalker, Dreadnought). Giving someone 5-12 life is much more problematic than a basic land (if they have it).
I'm not a huge fan of Wasteland in here either, except maybe as a 1-of to fetch with Knight to get rid of Mazes, Tabernacles, and Glacial Chasms. The deck simply doesn't have a plan to capitalize on mana denial. Most decks that do, play Daze/Spell Pierce or Trinisphere/Chalice. Alternatively, 2-3 Horizon Canopies in a 21 land manabase (+ Hierarchs) is a good idea because it guarantees you'll be able to cast your bombs if you draw them, but also gives you the option to cycle if you don't.
If you try out a "Big Zoo" variation, keep these points in mind.
If anyone's curious what the list I'm testing looks like, here it is:
4 Wild Nacatl
3 Noble Hierarch
3 Grim Lavamancer
1 Figure of Destiny
4 Qasali Pridemage
4 Tarmogoyf
4 Knight of the Reliquary
1 Elspeth, Knight-Errant
4 Path to Exile
4 Lightning Bolt
4 Chain Lightning
2 Sylvan Library
1 Umezawa's Jitte
3 Horizon Canopy
4 Arid Mesa
4 Wooded Foothills
2 Windswept Heath
2 Plateau
2 Taiga
1 Savannah
1 Forest
1 Plains
1 Mountain
With 1/1/1 Figure/Espeth/Jitte I have 3 late game bombs but they're diversified, so I never draw doubles. I've commented on why I like Figure so much in the past, so I won't rehash, but the idea is that he swings in for 2 damage past Rhox/Nacatl/mini Goyfs when you have 3 mana open.
Sideboard
3 Pyroblast (not Choke because I want to hard counter Jace and Show and Tell)
2 Krosan Grip
3 Pyrostatic Pillar (according to all my combo playing friends, this is the best option. nothing will stop them except for a faster clock)
3 Price of Progress (lands, control)
2 Tormods Crypt
2 Pithing Needle (Survival, Vial, Jace, EE, P Deed, etc. this card is hot right now)

