I currently pump, however, if I do shots I have to do two shots of levemir a day, plus injections whenever I eat, plus injections to correct whatever highs I had. Since I like to snack, that was like 6-8 shots a day.
There are two ways to think of insulin regimens- basal/bolus aka physiological, and standard, aka non-physiological. Your plan, as it sounds like you know, is a basal bolus plan. It mimics the way the body naturally makes insulin. Your levemir takes care of your body's fasting needs, and the rapid insulin prevents a spike from your food and can be used to lower a high.
Standard insulin plans that give two shots a day usually use an insulin called N in place of the Levemir. N is given twice a day and lasts about 12 hours with a huge peak at 6-8 hours. N can be mixed with other insulins. So, you take your N at breakfast mixed with novorapid or humalog or whatever. The N is covering your basal needs and the rapid is covering your breakfast. You get the huge peak from the N in about 6 hours. This is when you NEED to have your lunch, otherwise you'll go low. With dinner you take another shot. Again, it has to be timed about 12 hours from your last N shots. Again the rapid covers the meal and the N covers the basal.
Problems? Many. You need a very strict diet. Your activity can't vary too much. That second shot of N- when's it peaking? Why, that would be the middle of the night. The peak of N can vary when it happpens and how strong it is, leaving unpredictability in your bood sugars.