As a Jeskai deck, you have important cards for Workshops in all three colors, which makes the mana trickier. Ultimately how you build your sideboard is going to clarify things a little. Some things to consider:
I played a Grixis deck in many ways similar to this (with Young Pyromancer) at champs. I was happy with 24 total sources, but I would have liked space for 25. My curve was a little higher and I had more artifact mana, so you could likely get away with less ... but not much less.
When evaluating basics, you care most about the lands you need to expose early.
It's very reasonable to assume from this list that you would want to cast a Preordain or a Swords to Plowshares against Shops on the first turn.
It's also very reasonable that you would want to cast a Pyroblast on the first turn, but not against Workshops, and if you're holding up Pyro against an unknown opponent, you don't have to crack the fetch until you're sure what they're on.
Given this, Plains seems more important in your deck than Mountain. Consider, if you use a Volcanic Island to play a turn 3 Dack Fayden, steal a creature, and they Wasteland it, you're not really far behind ... you don't need access to more red mana next turn. If you use a Tundra on turn 1 to play a Swords to Plowshares, that's another story entirely.
Post board all of this can change if you're running cards like Smelt, Ingot Chewer, or multiple By Force. This in and of itself is a reason to run Fragmentize over Smelt, but there are tradeoffs there of course.
For a long time my Jeskai Mentor decks (pre-and post Gush and Mentor) have all settled on 2 Island, 1 Plains, 1 Mountain, and 4 Flooded Strand, 3 Scalding Tarn to find them. usually with the mountain in the sideboard. This is based on an anti-shops strategy of at least 7 one-drop white removal spells 2 Dack Fayden, 2-ish Jace, Vryn's Prodigy and 3-ish By Force.
I'm not totally convinced this plan is effective post Thorn of Amethyst however, and different cards require different lands.
With fewer Sphere effects post-Thorn, accelerants might be less important for a deck like this one with a fairly low curve. Still, 7 Spheres is a lot, and plays like Snapcaster Mage -> Abrade are pretty worthless if you wait until turn 4 to do them. I like having the extra Moxes but it's not clear. In the past I've run Sol Ring over an off-color Mox to punch through lock pieces, which is worth considering. Unfortunately Stony Silence adds a lot of tension to running more artifacts than you need to. Personally I'm not a fan of Stony Silence against Workshop decks and I would sideboard the card out ... whether or not you feel the same way will of course impact how many artifacts you want.
There isn't much to say here, your curve is pretty low which should help you. You're not running so many expensive cards that you need to cut anything just because of the mana cost.