Ok, getting back here for more feedback.
Have you tried
Ominous Seas before? I also like
Chasm Skulker.
Have you tried
Gamble? One of the few tutors in these colors. There is also
Long-Term Plans which might be a good fit for this deck since when you wheel it goes straight to your hand. Seems like a couple more tutors would help you access your win cons a litte more consistently.
Dream Halls and of course
Omniscience go infinite with your commander. I've always liked that interaction. I used to do the same thing in my Niv-Mizzet deck when I was running those and
Mindmoil. Dream Halls can just be a fun card in general, although it can totally backfire also.
I would maybe try
Fabricate so you can get
Psychosis Crawler and other stuff. A lot of times I would just get a mana rock with it.
Birgi, God of Storytelling // Harnfel, Horn of Bounty I think would go a long way in this deck. You can keep chaining spells for free off her ability.
Prismari Command,
Visions of Ruin and
Unexpected Windfall have been running great for me. The little bit of ramp they provide is quite welcome to get my commander out earlier.
Board wipes? I only see
Blasphemous Act I do think at least getting a
Cyclonic Rift would be worth your while, but there are other options too. I am liking the new
Consuming Tide.
Targeted removal? Where's
Reality Shift? I've also had success with
Reality Ripple since it saves your commander from removal also and stops combos. There's
Suspend Rapid Hybridization Chaos Warp
I think you should consider
Mission Briefing and
Shreds of Sanity they are two of the best recursion spells outside of
Underworld Breach.
Insight and
Mystic Remora are the two other passive draw enchantments that have played well for me.
You only have 3 counterspells and I question if that's enough. I think protecting Arjun and your draw doublers is going to be pretty important. I've said this before a lot but I really think izzet spellslinger needs those control spells. Thankfully there are plenty of good ones to choose from.
Swan Song Force of Negation Fierce Guardianship Deflecting Swat are all good fits I think. There are also some decent 1U counters like
Memory Lapse or
Delay if you are more on a budget.
Tibalt's Trickery is decent.
Narset's Reversal is great.
Possible cuts:
Aether Vial. I understand you're reasoning here, but honestly I think you'd be better off with something like a
Chain of Vapor that can bounce either your doubler or Arjun. I just feel like Aether Vial tends to be pretty dead unless you are in super dense creature deck and even then I would question it.
I'm not 100% sold on all your 0 and 1 drop artifacts. I know you are running them to trigger your commander for free, but I think you have enough 1 cmc spells to do that fairly efficiently anyway. I would just worry about these not doing enough on their own in a vacuum or early game. Running more ramp and interaction I think is more important.
Portent and
Sleight of Hand Both seem bad compared to other options. You mentioned
Consider and I think that's a great swap. But there's also
Careful Study and
Thrill of Possibility.
Visions of Beyond is also decent.
I kind of question the value of running wheels when your commander himself is a wheel effect. I think fattening your handsize would be more important so you get more fuel for your commander's ability. Giving your opponent's new hands isn't always a great idea. That's why I ended up cutting
Windfall from my own list.
Thought Reflection is an easy swap out for
Teferi's Ageless Insight.
Treasure Cruise - I've never like this card. I think it's bad. Mainly because it can't be reliably cast early game. You are going to get WAY more draw with a draw doubler in play and any of your cheap draw spells.
Pull from Tomorrow or
Sea Gate Restoration // Sea Gate, Reborn or even
Recurring Insight would be better imo.
Cloud of Faeries - doesn't really seem to fit? I know you are trying to get those free triggers, but I just don't see this having enough of an impact on its own.
Sunbird's Invocation - it's a neat card no doubt, i can see why would want to run it, but that cmc isn't great for the effect. We get a lot of card advantage in izzet already.
Inner Fire - I think this could be a different ritual. As much as I like the card thematically, I don't know if it's consistent enough. I think
Unexpected Windfall would be a better pick.
Fact or Fiction Expansion // Explosion higher cmc spells that I think could be something more efficient.