Hi,
Any House will do from an rp perspective, including Ex Misc. Bjornaer with a Heartbeast associated with building, such as a bird that builds a nest, beaver (yeah yeah) that builds a dam, etc. Criamon because good craftsmanship exemplifies increased harmony. Even Flambeau, for building weapons and war machines. And so on. Or just create your own Ex Misc tradition.
As for optimization...
Elemental Magic totally sucks, so of course it sucks for you too, but even worse since you are not likely to craft flames and wind very often. I and others have posted about this lackluster virtue before.
The most important virtue for a crafter is probably Cautious with Finesse, because all those stress rolls will otherwise catch up with you. You don't have it.
Also, be aware that RAW, crafting magic has a very hard time creating things that are beautiful. An extreme Finesse score is needed even to pull off barely competent art. So 3 vps go to Affinity+Cautious+Puissant Finesse. And then a lot of initial xp in Finesse. Beauty will still be hard to come by, but utility will be fine.
I might note that Terram is far from the only Form needed to be a generally good crafter: Herbam for wood and linen, Animal for bone and wool... Alchemy also falls under craft magic, but your magus might not care. Still, your magus might want to do something useful when not building a covenant worthy of Mordor.
Nothing wrong with concentrating on ReTe though. Regardless, we might want Puissant+Affinity with Rego, for 2 more vp.
So now we consider House, from the perpective of optimization. If your GM allows you to start with Mystery Virtues, I suggest House Merinita and Charm Magic ftw. A magus who crafts many different things might need to cast many different spells. Having these as Formulaic is a big waste if you only plan to cast them once or twice. Spontaneous Magic is better, if you can accumulate the Casting Total and if you can deal with the botch dice. Charms add directly to the Casting Total, so your magus can create a few up to his Faerie Magic score and then cast fatiguelessly. No chance of botch, though spell level is a bit limited. Decent scores in Phil+AL make ceremonial casting worthwhile. If you can take the Magical Foci minor virtue, that's another source that directly adds to casting total. Depending on GM ruling (I allow it but others don't), Cautious with AL applies to ceremonial magic, which lets you cast ritual fatiguing sponts for crafting; at that point, having extra initial xp to dump into Phil+AL is extremely worthwhile, which makes Good Parens, Baccalaureate, Gild Trained, etc worth attention. LLSM also deserves a look: Dangerous when used on the fly but not ceremonially, for you. (I've wanted to play a character that leverages all this...)
BTW, the right Faerie Correspondence can also make your day. I think the rules for FC need clarification and are ill- or insufficiently considered, but not quite broken. I love everything Faerie in AM, a preference that goes back decades (I'm gonna die...) because it connects the fake mythology of OoH with the real mythology and folklore of Europe. I also love optimized characters. So I also like FCs despite some issues.
My 'generic' optimization advice (Pu+Af in Te+Fo plus Focus as a base) does not apply here.
generic version
vp virtues
03 pu+af+cautious Finesse
02 pu+af Rego
etc
ritual spont version
vp virtues
03 pu+af+cautious Finesse
01 cautious with AL
03 LLSM
01 Charms
01 Magical Foci
01 Faerie Magic (house virtue)
01 Good Parens or Baccalaureate or Faerie Blood
If you can create an Ex Misc version of the Merinita, Strong Faerie Blood is a very very favorite of mine, which FC makes even better.
Anyway,
Ken