After L'Isle Jourdain, I was thinking of due south to Confolens, maybe west of the river, it looks prettier and might have a look at the Val de Vienne circuit if there's time, then alongside the Vienne on the D16, then finally SW along the N141 to Angoulême itself. I must admit that I'm just going by the map for most of it, but I spent a lot of time with a family in Chatellerault when I was a lad and we often used to go down the old tourist road, it was very quiet and picturesque.
But a house in Confolens, now that's a dream!