I transitioned to 5 days a week running for this training cycle and will keep that at a minimum. The plan is to use the beginner Hansons marathon plan for Dopey, so will have to transition to 6 days at this point if not before.
You won't need to do 6 days a week in advance of the 6-day a week plan. Doing 4 or 5 days per week is sufficient. Although personally speaking, I like running six days per week as things tend to feel easier on more days per week than less to me.
The idea was that a 10k plan will have more speed work style runs in a time of year before the temps/humidity become stifling. For the the HM plan, I was looking for one that just focuses on building mileage and not speed work. Once summer kicks in, I just can't push that hard. My T+D even in the early morning is 150-ish in the summer (July-Sept).
Does that seem reasonable? It's not quite what you outlined above but I also am accommodating southern weather challenges and trying to be realistic about what I can physically withstand in mid summer.
Totally reasonable. All factors should be considered when making these types of choices. In order to maximize your gains over a long period of time, you want to hit lots of different areas of the pace spectrum. If your plans are too similar, then you'll stunt your gains. For instance, my two biggest gains in fitness came from the move from 3 days per week to 6 days per week (dropped my marathon from 4:20 down to 3:38), and then was when I did a dedicated Daniels 5k/10k plan from his 3rd edition book in the Spring of 2017. I dropped my 5k time from 21:02 to 19:29. That came completely unexpected after thousands and thousands of miles of training on the legs prior. But it reinforced the methodology to me that you've got to diversify your training plans over the year. I highly recommend the Daniels 5k/10k training plans because they aren't the traditional 400m reps of 5k pace that you commonly see with "speed" plans. When you really dive into the literature it's quite interesting the variety of workouts that you can find vs the super basic ones you find online. I personally have nearly 40 different types of workouts now all with a different purpose:
Easy, LR, LR w/ fast finish, LR +Threshold, Progression, Blind Progression, Mini Progression, M Tempo continuous, M Tempo intervals, M Tempo w/ fast finish, M Tempo w/ Threshold intervals, HM Tempo continuous, HM Tempo intervals, HM Tempo fast finish, Threshold, Threshold + Mile, Threshold + 3k + Mile, Over/Unders, 3k pace, Mile pace, Critical Velocity, Crescendos, Crescendo Holds, Blocks, Blocks with rests, Valleys, Valley Holds, 5k, Minutes, Vigil Miles, Mona, Cutdowns, Hills, Pre-200s, Lumberjacks, Descending Specials Ks, Ascending Special Ks, Rat-A-Tats, and Fast/Steady/Blast.
Me personally, I did a Marathon plan for the Nov Madison M, now I'm in the middle of a 10k devoted plan aim towards the Princess Challenge, then I want to do some Daniels mile specific training in the Spring, the summer will be a brief down period, and then back into a 2022 Madison M training plan. None of these plans over the course of the year have the same types of workouts in them. The Madison M was M tempo focused, the 10k plan has been VO2max and LT focused, and the mile training will be anaerobic focused.