Mid-week is an ideal time to have a holiday. Places are not as crowded during the week, and it's a nice break from work/school that one would not normally have. It just seems a lot less stressful than a weekend and ends up being much more rejuvenating than a weekend holiday.
I like mid-week holidays because it makes the work week seem much shorter. I think that there is only 2 more days until a little break then two more then the week end. A weekend break still makes a 4 consecutive day work week seem much longer than it appears.
I feel weekend holiday does justice to your week long toil. You will whole heartedly enjoy the well deserved break after 5 days working. Moreover with out any gap/holiday during the week you will realize that you have put in some work. Mid week holiday will break the continuity of your work and of you seriousness. Additionally, people will be able to enjoy with their kids or friends or family as they would also be free over the weekends.