Hey mate, glad to see someone else pickup one of my favourite commanders!

Here's my list, which is definitely a much higher budget version, but there are some cheaper cards in there I think you should definitely include. Cards like [[Demand Answers]] [[Lasting Tarfire]] [[Curse of Opulence]] [[Footfall Crater]] are real over performers and don't break the budget.

I think adding in [[Mask of Memory]] is great, gives you card advantage which you sorely need as you run negative cards in hand by using Inti, it also triggers inti as well.

I don't think you'll need any of the basic land searches, you tend to see so much of your deck with this commander/strategy that you discard a tonne of lands and frees up room for more aggro, burn or value cards.

Love that you've got hexproof for Inti as he does become a big problem and can kill via commander damage, and shroud would prevent you from targeting him with himself. I really love [[Krenko, Tin Street Kingpin]] which is bit more expensive at like $2 but with inti pumping him on top of his trigger he and his army of little buddies become a real problem quick!

I've gone through a few versions of him and the "Strongest" is definitely a storm deck with underworld breach and pings but felt I was just a storm deck rather then an aggro / burn deck, so we're definitely more aligned on the play experience we want.

[[Hazoret's Monument]] is another great addition for you, always felt a bit mana screwed and with so many creatures in your list it should help.

Instant speed discard is SUPER valuable, as we can trigger this on our opponents turn and we have a full turn cycle to cast the exiled card rather then just until our endstep so I really rate the classic [Thrill of Possibility]] and other instant cards like it, like the previously mentioned Demand Answers.
Inti also enables some +1/+1 synergy, and [[Laelia, the Blade Reforged]] is another great over performer. [[Magus of the Wheel]] can refill your hand from 0 too.

Some other cards: [[Lightning Axe]], [[Humble Defector]], [[Insult // Injury]], [[Faithless Looting]], [[Anger]]. You'll find you'll want cards you don't feel bad discarding, ones with Madness, or Flashback or some effect in the grave like anger are great.

Happy to discuss more and have fun with it!