Viagrasaurusrex

Reclamation Sage should be in the sideboard(i know you have back to nature)
Sage is tutorable by chord and can smoke a connections from mono black, where as back to nature only hits connections sage can at least attack and if you don't need it you jsut dont chord for it.
I would leave back to nature in as it is amazing vs all the enchantment decks and auras.

Evolving wilds should be "shivan reef" This deck has a ton of colourless symbols so you really won't take too much damage from it.
Also holding mana up on turn 3 in an aggro deck isn't what you want to be doing.
burn spells(stoke the flames) and lightning strike would be a better fit.

Legacy Waste combo.

http://www.mtgvault.com/viagrasaurusrex/decks/waste-not-storm/

http://www.mtgvault.com/viagrasaurusrex/decks/burning-waste/

I feel that's the best modern can do, I am trying to brew a storm deck with waste not haha.
in both legacy and modern.

It's true^ a thoughtseize is a lot less fun when you have to pay 4 life instead of 2.
not to mention that extra tax on sign in blood and underworld connections.

Helm of Kaldra?

Name a format and I will do my best, it is hands down my favorite card. I also play 8-rack in modern so this card has been all over my radar. (picking up a playset today.)

Sadly it isn't legal today as I have a modern event after work -_- have to wait until next week to get solid testing in.

Yeah i can understand that, just mixing the two can combos can make you have less answers to different decks.
Still fine just means you get to pick and choose which one you go for haha

As for when to pod into what, it depends on which deck you're facing. You want a variety of different cards so you can pick and choose what you grab as you curve out. (Enter the battlefield triggers prefered)
You can also use phyrexian metamorph to copy birthing pod so you can pod twice in a turn.

There are two different pod list, each are very viable and they just have different match ups that they are better in.

Melira pod(Melira, seer, redcap/finks)
Melira pod has less disruption/removal in the main deck and can normally combo out earlier than angel pod.

Angel pod"value pod" (Archangel of Thune, Spike feeder) Normally runs 3x thoughtseize and 3x decay in the main which gives it a better match up vs some of the top decks like twin. With Angel pod you combo out by going infinte with Archangel and spike feeder. Its also a two card combo so its easier to set up.

It's bad if you can't flash it in as they will just kill it and then draw afterward.
But I mean turning rev into a lifegain spell and then attacking for 3 on your turn is pretty good haha.

Yeah, counters are a little worse when the enemy landed a voice on turn 2. Now you have to also worry about them chording into a Spirit of the Labyrinth in response to sphinx's rev.

Green/White can beat him pretty easy, most aggro decks can't though.

you just don't want to have him in vs most aggro decks because you have your walls to stablize, at turn 3 you want to leave counter mana up or divination.
and when you stablize he is a bad draw and warthing away a 3cmc creature is a lot worse than a 2 cmc creature.

wrench mind?
IoK?

Dakmor Salvage x2
When you have a rack in play(or carress, anything that causes pain on discard/lack of hand really) you can retrace raven's crime to keep them at 1-0 cards in hand.

http://www.mtgvault.com/viagrasaurusrex/decks/8rack/
this is my modern competitive version of the deck.

Yeah like either would be fine but dropping to 3 walls is probably better.

That should be fine, or elixer.

Its the choice between:
1. keep wall and have a better match vs monsters and aggro
2. keep elixer and have better late game draws/non-situational lifegain.

I can't forget about it, my meta has 3 boros burn decks in about a 20 deck meta haha.

I saw the below post right after i commented.

How do you deal with "Back to nature"?
If you don't play with other decks in mind it'll give you more bad match ups than you think.

Jace ult shouldn't be a last resort... The ult is the best part of the card and exactly what control decks want/need...
This coming from someone who Throughly enjoys playing control and has in almost every standard format.

R/U burn/control is normally called "Counterburn" btw.

^that won't happen in standard.