Last month I saw a dozen or so Holga photos nicely framed, matted and hung in an entry hall. They were wonderful and I even went back a few weeks later to look again and am trying to contact the Photographer to see what he did different.
I think what he did was what Sean is suggesting, compose loose and use only the sweet spot (or on a Holga that could be semi-sweet) and crop out the bad distortions. The images seemed like 1800 lens work or maybe very well done pinhole.
His use of two solid themes and very good presentation also turned "cheap toy camera" shots into something special. Photographer was Kyle Masuga about whom I know almost nothing except he is a Denver photographer.