With four or five days, you can take your time. You can alternate tasting days with freer moments, or extend your trip beyond the vineyards.
First, you can slow the pace : fewer visits per day, more time at the table, and a day to enjoy Bordeaux itself, with its riverside quays, its UNESCO World Heritage-listed architecture and the Cité du Vin.
You can also add a getaway :
The Arcachon Bay, for oysters, the ocean and the Dune du Pilat, the tallest sand dune in Europe;
Cognac, north of Bordeaux, to discover the region’s other great craft: brandy;
The Dordogne, for medieval villages like Sarlat and its gastronomy.
These extensions combine easily with the itineraries above, depending on your interests and the season.