Currently, there isn't a way to balance classes across blocks other than going into each course and choosing what block the course should have. It would be helpful if the algorithm tried to balance classes across blocks (i.e. 4 classes in A block, 4 classes in B block, etc. rather than 3 classes in A block, 9 classes in B block, etc.)
This is essential for a good schedule maker. And student requests should be the #1 priority for determining where singletons and doubletons should go (after room and teacher availability is set)