First of all I would use more contrast in the filling/contrast with colours. With the dark filling it's harder to tell the letters as the line aren't really visible on some points. Second I wouldn't add to much, the white parts are very thick, personally I would make them a lot smaller so they are just a nice detail. Also I would choose where to add what better, now every letter has that extra kind of blob. But because of that you could also cause confusion, second and third letter could also be seen as a B and the A as a H.