I’m doing a similar thing myself. I find that the mostly body weight strength training as found in the TfNA and Uphill Athlete books are now working for me. I’ve been following Dan John and have worked with Pat Flynn through personalized online coaching to build my strength up. I find working with kettlebells and barbells and abwheel to do more for my cardio than purely running ever could.
My experience of the protocols put forth here is that they are best suited to those with extremely limited equipment and a highly developed level of strength already. And the routines developed are going to keep people at or near that high level. As for me personally I was always much to weak physically and weights have been instrumental in my journey to becoming a better ski tourer and hiker in the summer. I’m not nearly as tired after a hard uphill session and my form doesn’t break down nearly as often especially on the downhill.
So many benefits to be had from being overall stronger and I think there are more foundational ways to do it. Lift heavy things, then lift a heavier thing next time. Repeat.