Class Features
The basic stuff is to be expected. Though Con/Int saving throws is unique.
It's a rogue with more defense. Though the reliance on crossbows leaves me wondering about their Bonus Action economy, I have a feeling it wont matter in the long run. Oh, and as an option, they can use guns.
Magical Tinkering
If there was ever an example of magitec opulence this is it:
The magic way to send Text messages, selfies, and even stink bombs. I can see this being used for oodles of flavor and humor.
Spells
They follow the Cleric Method of spell casting. Pick a few of the spells from the entire list available per day, and also ritual casting but only of spells you have already prepaired.
They also use INT, which is nice, INT needs way more love, but it's totally expected.
The real interesting thing here is that this is a half caster with cantrips! Finally!
Cantrips:
A combination of Wizard and Druid! cantrips. Though I would have used Produce Flame instead of Firebolt.
Level 1
No direct offensive spells. There are a lot of buffs, detection, a smattering of area denial, and some restoration here.
Cure Wounds over Healing Word is an interesting choice. I suppose they couldn't justify the less tangible Healing Word.
Level 2.
Finally a spell that can be used to apply the hurt, but otherwise the trend continues.
In fact, outside of getting Fabricate and Creation, the spells are basically the same but better from here on on. Not much to comment on other than the fact it gets all of the essential healer spells, except for Remove Curse, which it should totally have because it fits perfectly.
Infusing Items.
They fixed the bug where your class features could be permanently stolen from you. Which is nice.
Other than that, they are basically Invocations that you can share with your party, with the additional bonus of the items being semi-swappable every day.
It is a bit odd that the +x weapons and Armor only go up to 2, but then again a +3 item is legendary.
Tool Expertise.
Lets you keep up with the Rogue in the disarming arms race.
ASIs
Everyone gets them.
Arcane Armament.
This is an oddly specific take on the extra attack feature. One that is easily overcame mind you, but still really damn weird considering they are meant to use Crossbows of all weapons. It's a pity they don't get a bonus to Cantrip damage, or something akin to Divine Strike instead.
The Right Cantrip for the Job
A Wizard would kill for this. In fact, put this on the pile of features I earmarked for the Generalist Wizard.
Spell-Storing Item.
This is a capstone-esque ability that lets you finally share your spells with your group. Or just get 5 extra low level spells per day. Either way it's rather boss.
Soul of Artifice.
Because having one capstone wasn't enough!
Not only do you get to attune to 6 magic items, you get a +6 bonus on all saving throws!
I'm just going to say this ability needs some heavy retooling. Drop the bonus to saving throws, and make it come online somewhere at the end of t1 or beginning of t2 so that the artificer can use the goodies they are making.
Subclasses.
Alchemist, for those who want to be party support.
They get skills to use the proper tools. Of note, you are intended to craft potions with this subclass.
An expanded spell list that has some OK options.
It gets better healing powers, a bit more acid/poison damage, and a familiar that would make a Beastmaster Ranger cry.
Artillerist, because the boomstick subclass wouldn't fly in Eberron.
The tools are technically worse, but you get to use Wands, Staves, and Rods as compensation. Also, you are supposed to craft permanent wands with this subclass, but good luck with that one.
Speaking of wands, you can use them to cast [-]Any Cantrip In The Game,[/-] any artificer cantrip, even those you don't know, with a damage bonus.
[-]Did you want to Eldritch Blast like a Warlock? Good news! Really want to pick up Druidcraft because you like flowers? No problem! [/-]
~~~I stand corrected, apparently I didn't catch the restriction the first time around~~~
To hammer home the idea that this subclass is all about the spell booming, you get Fireball and a selection of other destructive spells. And also Shield, for reasons I'm not really sure of, but then again the base class should have gotten that spell anyway.
Now, the really fun part about this subclass is the Arcane Turret, which is a walking Flamethrower, Laser cannon, or force-field generator, with the option to self destruct, and be resummoned with a spell slot. It's a lot like a Spirit Totem from the Circle of the Shepard, only more explosive.
Over all, the class sounds fun, but they aren't even remotely tooled to be an Attack-Action class, despite having class features intended to back them up.