Yes, the extra blocks are to provide some more flexibility, creativity, and experimentation in the puzzles!
Initially, I put only the blocks required to create the solution that **I** came up with, but in some early playtesting with friends, they found solutions that would have been possible given a few extra blocks! I thought that their solutions were equally valid as mine, so I started adding a few extra of each "minor" type of block (the L's and I's), because they don't really change the ability to loop a path. They just allow for different shapes within the same "topology", if you will.
I also found for some levels that being able to assume all blocks would be used allowed for some logical inferences that were a little too strong for the difficulty I wanted the puzzles to have. Demonstrating early on that blocks would be left over meant that players have to think about what path they *want* to make, not what paths are *possible* to make!
Also, some other feedback I got is that I could have a final "you used X blocks, but there's a solution that only uses X-1 blocks!" note that might be fun for the players that like to optimize.
Thanks for playing!