With Craft Magic, my group uses Finesse/3 rather than Craft/3 for the limit of quality. This puts a reasonable cap on the maximum quality while avoiding limiting most Magi to only being able to create Superior quality items. Most Magi will completely lack the craft skill, with a few having a point or two to give the familiarity bonus.
Overall craft magic is such a difficult and painful mess that most people I have played with have not wanted to use it without HRs. For example using the "Desired Craft Level" (C&G, p 67) with modifiers for Time, Familiarity, and "Done with Magic" (the +3 by RAW) as the target for the Finesse roll.