Arensen

Hmm. I hadn't noticed the Tolaria working as a tutor. That means you're effectively running six copies, which is plenty. My mistake.

Any comments, suggestions, or improvements would be excellent.

Hmm. If you're pushing for a strong competetive deck it will need some work, but the framework is here for a strong temur monsters deck. For a start, is this a budget deck? What sort of money do you have to throw around on cards?
Second, do you want to go competetive, or play casually? Both of those will change the kind of deck it will turn into.

I love the idea, but I feel like if the deck has a reliance on The Tabernacle at Pendrell Vale it should run three of them. They are legendary, but you want to draw one each game.

I would also be running Monastery Mentor as an addition or a replacement to Mantis Rider. It generates tokens at ridiculous rates, and can easily take over entire games on its own if it goes unanswered for a couple of turns. Your deck looks a lot like a Jeskai tempo deck with a few token generators. I'd maybe cut the Chandra Pyromaster, 2 Magma Jets and a Mantis Rider to add 3x Monastery Mentor and a fourth Stoke the Flames, because those cards are crazy. Also, if your budget stretches to it, I'd run scry land and fetch lands instead of the lands that heal you. They both come into play tapped, but the scry lands give you good consistency and card quality, which is vital if you are playing the quick aggressive game that Jeskai decks should.

Are you sure that you need to run White for this deck? I assume that it's for Path to Exile, Verdict, and Artifact hate. Running black instead gets you the Fae tribal land. In terms of sideboard option you don't really lose out by running black, as you now have access to damnation as mass removal, dismember and doom blade for spot removal, and thoughseize if you wanted to take a more controlling attitude. Unfortunately, this doesn't solve your troubles with Affinity as you have only hurkyl's recall and thoughtseize to deal with it, so you'll want to decide exactly how much of a threat it is.

Is Myr Reservoir, Myr Turbine or Myr Matrix a better option?

I think that if you took 2 Coat of Arms and 2 Door of Destinies, your mana curve would fit Wolfir Silverheart x2 well enough...

I'd also suggest adding a few more lands, I think that 22 Lands is slightly too few.
If you went to 24 I think you'd have just a touch more land consistency, and you do have Trade Routes to deal with dead land draws.

I'd choose Colossal Whale as a Finisher these days.
Both helps with the control and kills people quickly.

Dimir Charm are both Control and Mill at the same time, I'd pcik up some of these if you can

Tribal Wolves.
I love it.

The only thing I recommend for this deck is Wolfir Silverheart for a quick way to end the game.

For a dedicated Rakdos deck, you're remarkably low on creatures...
I'd also remove anger of the gods, because you don't want to be wiping your own field.
You could replace it with Rakdos cackler for more dedicated aggro if that's what you're aiming for.

I suggest Blasphemous Act.
It does a similar thing as Shivan Meteor, but also serves as board wipe if it's needed. 13 damage to each creature, if your opponent has curse of the Bloodletting (which they should) quickly reads as insta-kill.

I love spitemares, I think they'd fit perfectly.

Looks solid. Your mana curve is well set up, with a nice curve of Nightveil Specter into master of waves.
I'm uncertain about the dissolves however. I'd suggest taking removal instead of counterspells.
Just my opinion.

You know, I really love this deck.
While may want more Fireballs, it's decks like these that make me love MTG.