That would be a lovely trip over three weeks, but you would need to it schedule it out in a little more detail. Not necessarily to the mile/day, but you will want to say how many days you'd like to spend on each leg. e.g. how many days is 'a few days'?

I rarely plan anything much, but mark on my (paper) maps where I want/need to be on certain days/dates. Then break the rest up so that I stay on-track.

Great trip. Enjoy!

Lifey