I recommend buying a book about picture frames to help you out. I bought two, and have read one so far. I notice that most of these books spend their time discussing and showing a great deal about matting boards, cutting, mounting, etc. but little time on the frames themselves. But they do have a few ideas.
I think it would be easy to make simple frames with what you have available. If you do not want to do the miter cuts, then simple butt joints could work too. Half laps could also work, and you could leave the frames extra size to get a more arts and crafts design.
I think the more difficult part is to make an attractive design on the frame itself. I have not found that right combination yet of router bits and such to make an attractive moulding. When I get done with my latest frame, I will post some pictures for everyone to critique. I find the Lumberjocks give me lots of ideas for future improvements.
Let us know how this goes Mike. I say you should build the frame for your friend and see what happens. Never know, you might be in the framing business soon, picture frames that is.
-- Bill, Turlock California, http://www.brookswoodworks.com