Four one-week bases, designed to feel varied and unhurried while you still travel completely independently.
Use Tywyn or Aberdyfi as an easy first base. Walk the coast, take the Talyllyn Railway, explore the Dyfi valley and give yourself permission to do absolutely nothing for an afternoon.
Move inland for a week based around Eryri. Mix bigger days with easier lake walks, heritage railways, village stops and drives that are half the point of being there.
The third week changes the mood again. Think small harbour towns, beaches, sea views, cliff walks and evenings that naturally run a bit longer.
End with a gentler kind of drama: rolling hill country, market towns, country pubs, cottage views and the feeling of winding down without the trip losing momentum.
The best bit of a slower route is that every week has room for both plans and spontaneity. You can do the famous things, then still have time to find your own favourites.