spell for moderation - conjure a boat from water

hi folks,
A spell for moderation, for comment and banter. The basic effect is to transform the air into a room, which can be used to camp in overnight. The concept started as a magus who can travel light and conjure many of the comforts as needed. A typical Tech would be Creo, but pondering that Muto might be used to transform air instead. Yes a little more obtuse, but seems legitimate compared to some of the cannon effects which transform fire to stone, etc. I can't remember he effect from a sourcebook where the Muto magi formed a tent, or what it was formed from, but it rings a bell.

Draft spell so far:

  • Base effect for Auram is a single phenomenon, up to 100 paces across. That would appear to be plenty. My reasoning is that a mtuo spell which converted a stone tower to air would create a fair volume of air, but not a huge storm worth. So that same about of air is needed transforming the other way.

  • R:Touch is enough as a spell can effect an entire Target as long as a part of it is touched. i.e. you don't need to touch all of a man to affect them.

  • Base effect for Terram is 10 cubic paces of dirt, which is not enough so a +1 mag grants up to 100 cubic paces of earth.

  • Convert the dirt base to stone, which is a +1 mag modifier.

  • This is enough earth for a two rectangular rooms with walls 4 paces wide by 3 paces high, and half a pace thick (6 c.p each surface x 6 surfaces for the first room + 5 surfaces for the second = 66 c.p). Then add some reenforcing to the walls, a small battlement on top, and miscellaneous internal features.

  • More complex than a bridge or wall (which do not have complexity modifiers in the rulebook) but not ornate or as expansive as a wizard's tower.

I then got to thinking that an effect that lasts Sun is only 5 levels cheaper than moon, so perhaps D: Moon would be handy for other purposes. I'm still pondering if I should write it up as Sun or not.