Thank you for posting your sudoku site. I played through 1 game on easy. I found it to be an intuitive interface. One suggestion I have would be to possibly change the text on the 'Enter Hints' button. I was expecting the board to give me hints about where to put the next number, but it's really an opportunity to write notes into a cell. I would change that button to say 'Enter Notes' or something like that. Other than that, everything else seems to work pretty well.
Building online resources for sudoku beginners.