How about you give me a list of meals, I pick 50 or 100 of them, and then you give me a shopping list for the month including where to get it at the best price, taking advantage of bulk purchasing and overlapping ingredients. Then email/text/notify me every day with the recipe for dinner that night. I'll keep the left overs and use them for lunches.
This should minimize time for planning and cost of meals, two things Blue Apron largely fails to do.
It'd also be nice if I could get a further notification asking me how long it took me to prepare, so the service can get an idea for how long it takes me to cook and help me plan dinners accordingly - maybe giving me faster alternative alongside the normal dinner plan.