Break your years up into two equal segments, with a pattern within each segment as follows:
First 6-8 weeks: Start at just under half and build to just over three-quarters the volume of running you’ll do at peak, with an emphasis on a non-running area of weakness (heavy lifting, yoga, etc)
Next 6-8 weeks: Build from three-quarters peak running volume to full peak running volume, doing some light intensity (hills, fartleks, fast-finish long runs, strides) while still doing the non-running activity regularly
Next 4-6 weeks: Add intensity to your running (tempos, cruise intervals, occasional VO2 max workouts) while maintaining near-full volume and backing off substantially on the non-running activity
Next 3-4 weeks: Drop your volume back to three-quarters peak and do regular high-intensity workouts (VO2 max work, true speed workouts, hard tempos and time trials—I know you said you don’t have any races planned, but maybe hop into a couple unplanned) while foregoing the non-running activity entirely
Rest for 1-4 weeks, only running and/or doing serious non-running activity when you want to, in a non-regimented fashion
Wash, rinse, repeat. You’ll come out of 3-4 cycles of this with a strong foundation for whatever kind of training you want to do next.