Here’s what I would do. Pick a goal marathon and work backwards. Give yourself 16 weeks for fully focused training, or a structured plan. During the weeks(8-12) prior to that, Make that your “prep” phase. Kind of what Zeke was talking about. Get the miles up gradually, work in some strides, flexibilty, strengthening stuff…..get your body prepped for your training phase.
I also think you are still on that “learning curve” …you have put in miles, but you are still new at it so you aren’t getting all the benefits yet. Remember, its all money in the bank, hay in the barn…..or insert favorite cliche here_____________________________.