This is a modification of a previous work of mine I posted on the r/Magicdeckbuilding subreddit (since it was FAR from being competitive), and took some inspiration on an aggressive UR Emry deck (the link to which I can't find right now - I will edit this post as soon as I do). It's a midrange artifact-based list that wants to end the match with, ideally, a 6/7 flying double strike trampling hexproofed dragon (that sounds SOO Timmy). We have answers for just about anything (though some are sideboard-bound).
Now, the gist of it is simple: play Emry, get a steel overseer, grow your artifact creatures (mostly it, owl and occasionally an animated artifact). Simply getting two turns off of steel overseer is usually enough to secure a match, especially with an accompanying owl. If the match is lengthy, then we bring out the big guns: Fires of Invention. This card gives the deck sooo much in terms of tempo. We're not casting cards constantly, so the limitation will not affect us too much (though if we do run out of fuel, it hurts a bit to have to (re)cast a wishing well and pop it open). Shimmer Dragon is an obvious draw engine that feeds off of our passive artifacts (glass casket, crystal slippers + sideboard) while also being a hard to remove threat. Karn and Ugin have similar roles - card advantage + threat deletion. Karn can fetch the ideal answer to a problem while giving us our embercleaves - more on that later. Ugin also makes our Golden Eggs free to cast, meaning you get to cycle through the deck while getting some mana fixing (very rarely relevant) or life gain (relevant vs RDW and BR aggro). Crystal Slipper may be a contentious add to the deck, but giving an overseer or emry haste is very relevant and powerful.
The main reason to go Jeskai rather than Izzet or Azorius is Danse of the Manse and Embercleave. The former lets us recycle just about all our artifacts without losing a turn (as long as fires of invention is in the field), while the latter turns anything into a threat - and is downright deadly on a Shimmer Dragon.
The rest of the deck speaks for itself, mostly. Glass Casket handles Simic Flash, lava coil takes care of Questing Beast. For the sideboard: Grafdigger's Cage, while anti-synergistic, can stop decks that rely heavily on their graveyards (Izzet Phoenix being probably the most prominent currently, but I'm sure new strategies will emerge). Embercleave is embercleave. Bag of Holding is protection vs discard heavy strategies while letting us cycle past drawn repeats - unfortunately it exiles, making Emry and Danse potentially weaker; Manifold Key boosts Steel Overseer and can be a finisher as well; Meteor Golem, while expensive, deals with just about any threat - and is free with 7 lands + fires; Sorcerous Spyglass is a considerably cheaper shutdown for planeswalkers; God-Pharaoh's Statue puts a stop to many strategies and severely hampers their game plan; stonecoil serpents to bolster our field, and one extra witching + 2 casket for situational usage.
The deck seldom runs into any mana problems. The most common occurrence would be having one of the scry lands on t4 with a fires in your hand. It's actually quite possible to outright remove the shocks from the list and still have a relatively decent flowing deck thanks to the scrylands and Fires, if you're on a budget.
Now, I've made it clear in previous posts here that I'm not the best at refining decklists. This has gone through a couple variations (including gingerbrutes for an aggressive take, or mizzium tanks for an unexpected play) and this, I feel, is the most refined list I can make. I've had moderate success versus Simic Food and Simic Flash, some draw dependency vs rdw and rakdos (but once we establish control, we usually win), and a bit of weakness to monob, but not enough to show a statistically-significant winrate.
The main consideration I'm making right now is about Steel Overseer. After so many changes, its reach was considerably limited. It's still relevant, mind, especially when we need to +1 karn, or want to grow one of our owls. But I think the deck could make better use of another card, such as Corridor Monitor or mainboarding Stonecoil Serpents.