We have tried various times and days. For me personally, if the run was any other times other than either Tues, Wed, or Thurs, I would really never be able to attend (yes its possible to attend even less than I do right now).
On a less personal focus, the times we have made efforts to include weekends etc, the runs have been less successful than they are today as far as attendance goes.
I understand if you chose to do another type of run other than this one of course, but really, I don't see changing this ones timing much, as that has failed in the past several times.