The crépes look good. However what is the point of the starter? It is not a dough that requires any type of levain or yeast.
Did you let it ferment in the fridge? With the eggs and the milk it can't be on the counter top.
Its essentially Twofold, taste and texture. My levain is mild and tastes fruity which i believe contributes to the overall flavour. I've been feeding my culture with Caputo 00 since day one and the recipe is 100% Caputo 00 so i believe this gives the crust a good uniform colouring and appearance. I believe using Caputo 00 in crepes is also forgiving, in the sense that it gives me much time top my crepes and not over-burn the crepe.
I have kept some leftover batter in the fridge to test any difference in the outcome. First of all, I haven't seen any difference in the batter, neither thickness nor volume. Second, The smell didn't change and kept its pleasant scent. The only noticeable difference comes when spreading it over the griddle, Least to say, it is not as easy as it was in the beginning. Also there is some texture difference as the browning is more evident as you will see in the pictures below. With regards to taste, there is no noticeable difference.
The crepes cones you see are a Japanese variation with homemade banana ice cream and Nutella.