I just love the blueberry strawberry combination, but you can use any kind of fruit you like. Just like you can put any fruit in a pie, you can put any type of fruit in a galette. So if you want to experiment with this blueberry strawberry pie, substitute another type of fruit for one (or both) of those ingredients. Blackberries or cherries would be good or consider a firmer type of fruit such as apple or pear. If you want to try this recipe using cherries, look for pie cherries, which are also known as tart cherries or sour cherries, and remove the pits of course. Peach would also be nice and give a contrasting color.