Dave:
FOLLOW THE ME PLAN’S PROGRESSION. The early workout are just samplers of what’s to come. I promise you good results if you stick with the progression.
You certainly can design your own. I’d run through this one first to see how it effects you. We here at UA have used this with everyone from US Navy SEALS, world class mountain runners and alpinists, amateur Everest climbers down to those hoping to summit their local mountain. It works and has given good results for over 30 years for many hundreds of athletes.
The main thing we see is that Fast Twitch athletes get much less muscle soreness with these workouts than do ST folks.
Give it at least a few weeks and see how the progression feels then.
Scott