Congratulations on beating the game! I'm really glad that you enjoyed playing it! Those 9x9 puzzles definitely gave me a fair amount of grief during development, so it's good to hear they weren't a complete cakewalk!
I had estimated it would take somewhere in the range of 25-35 hours to beat all 300 puzzles, so I'd say that's a great time!
And email is absolutely fine! =)