DedWards

If you'd like other ways to cheat the big Elementals in, Through the Breach and Mindwrack Liegecan assist with that. I'm aware that they cost 5 and 6 mana respectively, but they do have up sides. Through the Breach is both an instant and grants haste. Mindwrack Liege can drop either creature at instant speed, doesn't force you to sacrifice it, and gives +1/+1 (neither are both the Liege's colours).

I have also seen Doomgape run in this type of deck. Between Incandescent Soulstoke's ability and Smokebraider supplying any colour mana, Doomgape not being red nor blue is almost meaningless.

You need double strike, it'll win you more games. Temur Battle Rage fits the bill.

Sorry, I saw green in the deck's colour indicator, but didn't look at the name of the deck (or its land base), my bad.

Bioshift moves +1/+1 counters around and targets two creatures for one mana.
While it requires 2 green, Setessan Oathsworn is too good not to include.
Rancor is Pauper legal as its original print was a common.

With all the fetch, I don't see the need for 4 Rogue's Passage. 2, maybe 3 would be good and free up a slot for another forest to increase the chances of playing your green cards more reliably.

Murderous Redcap <- there's you damage piece of the combo.

Maybe move Flame Slash to sideboard and put the Charm in its place?

I'm actually in the process of acquiring 2 Chandra, Flamecaller and a 3rd Omnath in trades. Chandra's +1 plus Omnath's trigger for Elementals dying is going to be fun. I know that they get exiled if not killed, but with Omnath out, whether or not they get killed, it's 6 damage :D

Boros Charm?

Not bad. Sounds about the same as my Omnath landfall deck (no Eldrazi at all in mine).

I do have a question. About how early can you get one of your big threats out?

What's the problem with adding the Wastes? I just tested it and they add properly

Just remember, Arbor Elf can't untap Nykthos, Shrine to Nyx.

If you can afford to get them, 2 or 3 Nykthos, Shrine to Nyx will help a lot.
Voyaging Satyr acts as Arbor Elf number 5-8, but unlike the Elf, the Satyr can untap Nykthos.
Some of the hybrid creatures from the Lorwyn / Shadowmoor block might interest you. Wistful Selkie draws you a card when it enters the battlefield; Wilt-Leaf Cavaliers is a 3/4 with vigilance; and Boggart Ram-Gang is a 3/3 with haste and Wither.
Strangleroot Geist has Undying, so it'll stick around a little longer than the rest, supplying its {G}{G} even after being killed once.

Just because I don't have that many fetch and shock lands, doesn't mean that the deck can't be competitive.

The slot was a toss-up between the two. I settled on the Drone for the deathtouch. Though, maybe I should move the Drone to sideboard?

Oh ya, Evolving Wilds help with landfall triggers too.

Your choice of land search doesn't quite fit the creatures that care about it. You want to use cards that put at least some of the lands straight onto the battlefield, like Nissa's Pilgrimage. Explosive Vegetation is another one you should play. Here are my reasons why the ones you've chosen aren't good:

Firstly, Loam Larva is possibly the worst choice in land search. Not only does it not put the land onto the battlefield, it doesn't even put it into your hand. Additionally, because it puts the land on top of your library, it screws up your draws. I'd replace it with Leaf Gilder, which helps you play a lot of your other cards a turn earlier.
Next, Sylvan Scrying. Don't get me wrong, this is a great card, but because it puts the land into your hand, it's not optimal. Remember you want the lands to enter the battlefield asap. to activate all the juicy landfall triggers.
Lastly, Natural Connection is only good because it's an instant, but because Nissa's Pilgrimage and Explosive Vegetation fetch multiple lands while this only fetches one, it's the third card I'd look at swapping out.

Also, because you only really have one way to give Baloth Pup a +1/+1 counter (Retreat to Kazandu), it's not helping your strategy.

Sprout Swarm is by far the best Saproling production spell.
Scatter the Seeds isn't bad either.
Look up creatures that get spore counters (most are of the Fungus creature type).
The Supply half of Supply // Demand is good too.

Purphoros is legendary, so you can only have one out at a time. Impact Tremors and Outpost Siege (calling Dragons) can help you get multiple instances of damage.