Very budget, had to work off of what I have.

Plan on getting rid of Flames of Keld, Lavarunners and Firebrands, Opting in for more competitive cards

I overall really like this list...ive been on a red deck wins kick lately and I think it looks pretty good!

I think I like Kumano Faces Kakkazan  ^Flip or even maindecking Roiling Vortex over The Flame of Keld.

Maybe consider Dragon rage channeler over Ghitu Lavarunner... Goblin Guide over Fanatical Firebrand...

Other good cards in the Modern pool is Lava Spike, Rift Bolt, Vexing Devil...

the big expensive cards for mono red is probably Eidolon of the Great Revel.... or Ragavan, Nimble Pilferer

Updates:

I somehow managed to go 2-2 in my local tournament, 1st day playing the deck, I was very impressed with its killing power.

Goblin Guidex4 => Fanatical Firebrandx4 Fanatical is a good cheap option. However, I found that goblin 1 red mana for 2/2 KILLED other opponents. This single card actually led people to discord A LOT of cards. Which helped me. MAY look for a replacement in the future. (Ragavan, Nimble Pilfererx4, If I ever get rich)

Ghitu Lavarunnerx2 => Monastery Swiftspearx2 No explanation was really needed, it was really just a cheaper/crappier version, managed to find 2 more at the store.

Goblin Chainwhirlerx4 => Kumano Faces Kakkazan  ^Flipx4 Goblin Chain was OKAY, there were 1/2 times where it actually did so much good. BUT, Kumano is cheaper, (does almost the same thing Chronicle 1) and also turns into a 2/2 and gives a creature a counter if you've summoned one on that turn. Which with this deck is likely to happen.

Magma Sprayx4 => Lava Spikex4 I'm not really happy about the limitations of either of these cards, But Lava Spike helped against planeswalkers and also make it easier to kill the opponent.

Its really hard for me to tell if it is a good idea to keep Tormenting Voice/Cathartic Reunion OR The Flame of Keld

I found that the Flame of Keld's draw power was enough to get me through some situations. There were moments where I wish I didn't have either a Tormenting Voice or Cathartic Reunion. This showed some flaws while facing players with counters.

as recommended by Tcbrgr Vexing Devil Or Rift Bolt would be good replacements.

Update PT2

I ended up Choosing Kari Zev's Expertisex2 to replace Shrapnel Blast

Straight up won a round by stealing a red creature from someone while the 3rd chronicle of The Flame of Keld was an active, decent combo.

Sideboard coming soon.

Potential Replacements for Tormenting Voice and Cathartic Reunion

Experimental Synthesizerx4

Underworld Breachx2 with Gut Shotx2 (maybe replacing Karl Zev card too)

Aug 8th, Record 2-2 60% Game win rate (6-4)

Strangely enough my shop didn't have Experimental Synthesizer Before I started today I had already bought 3 Gut Shot and 1 Underworld Breach to replace my Tormenting Voice and Cathartic Reunion

2 things I've discovered this evening. My deck is SUPER good with 2 mana. Most games were either 1 turn away from me beating them. Or them just Combing me to the end of existence by turn 4 (literally in my last round). I won 3 games today with only 2 Mana.

The other thing. Dragon's Rage Channeler is good.

I seem to do OKAY with most other decks, and REALLY well with control-y types.

Also with the abundance of shock/fetch lands nowadays I basically have to do about 14-16 damage in a game. But it ain't easy with some of these decks.

Anywho.

CHANGES: Sideboard Blood Moonx2

I wanted to be that ONE special red deck that doesn't need this card. But it really does need it. There are WAY to many decks out that this shuts down (pretty much instantly) Will plan to buy more as necessary

Underworld Breachx1

Unfortunately, I don't have a million dollars, or I would buy more of this card.

Pyroblastx2

Screw blue. Red also need a counter against black -.-

FROM MAIN BOARD

Kari Zev's Expertisex2

The amount of compliments I got playing this card was amazing. Pay 3 Mana to take control of a creature and then play a free card (basically with the majority of my deck being <2 mana) In the words of one of my opponents "This is the perfect cheap replacement and fits your deck SUPER well. Good thinking"

The issue is, It is WAY to situational I really wish this was an Instant. Would make this card 10x better.

SIDEBOARD CHANGES OVER MAINBOARD

Dragon's Rage Channelerx2

Again, only found 2. Need 4 likely. If I do this, might have to rethink some other components. Maybe not.

- The Flame of Keldx3

I loved this card too. But it is way too situational. And the only real benefit is the 2 cards. and it takes 2 turns to get them.

Lava Dartx4

I was extremely lucky to have someone gift me a playset of this card. I bought the dude a drink after. Was great.

Post Update:

Didn't realize Pyroblast so scratch that

This looks like is really coming along nicely! I'm curious how Bomat Courier is performing for you? I have always been afraid to try it myself.... Underworld Breach is an amazing idea too!

I also see you are really heavy on the 1 drops.... I dont know if Chalice of the Void is in your meta or not but id Highly suggest Smash to Smithereens as a sideboard option.

Bomat Courier has been doing okay.

I feel like that will likely be the next card I replace, or trade out for more Dragons Rage Channeler, another Gut Shot and another Underworld Breach

To be honest my local meta is very weird. It's a bit smaller than most I think but Smash to Smithereens was the card I was going to comb through my collection to find. Because I knew about Chalice of the Void but haven't seen it yet.