I don't think Artificers as Mages would work -- Leaders are defined through their class features, but controllers are defined through their powers. So an Artificer Mage would -- unless they were unable to use wizard powers (in which case, what's the point?) be able to hit like a controller by heal like a Leader. I don't think any Mage build has -not- been a controller; the closest is the Blaster Wizard (mostly the Genasi Blaster), but she has to give up controller powers to blast better, and multi-target blast is in-role for a controller anyway.
Artificers might actually work well as a Swordmage build, actually (or really, just make them both subclasses of Gish). Both classes are focused around using both weapons and Arcane magic, and the meat of both defenders and leaders is in their class features. So making an artificer a Swordmage build would mostly let them poach powers back and forth--which given the limitations in question seems totally fine. Even having different implements would be fine; it's not really a problem if an Artificer "swordbursts" with a wand instead of a sword, or a swordmage enchants her armor as Flameburst using her sword.
Of course, one would want to make Magic Weapon a class feature power, not a Gish 1 -- it's a defining (and OTT) power for the Artificer.