Given the distance some guests will have to travel (a 7 hour round trip in a day is a bit much, IMO) I think a mid-week wedding is slightly inconsiderate. If it was an evening wedding, in a town where all the guests lived, I wouldn't have a problem with it.
Regarding inviting your FSIL's inlaws, I'd definitely push back on that one. Would your MIL be amenable to hosting a nice dinner for them and you, after the wedding? That could be a good compromise.