I see... Nevertheless I think it would be awesome as a released app though
I'm also currently trying to make a puzzle generator for my sudoku/kakuro hybrid puzzle game, but still couldn't get an optimal one; since it's basically a 7x7 sudoku where 5 numbers in the row is fixed (5-6-7-8-9), the last 2 is not (can be 1,2,3 or 4). The generator still uses a lot of loops, and sometimes fail to create a valid board, also I still have problems with the elimination process so I end up clearing the cells manually to make a valid puzzle. Maybe you'd like to have a look at it sometime?