Congratulations! Hopefully you should now be more familiar with your Kali Linux system and you should not be afraid of using it for any experiment that you can think of. You have discovered its most interesting features but you also know its limits and various ways to work around those limitations.
If you have not put all features into practice, keep this book around for reference purposes and refresh your memory when you are about to try a new feature. Remember that there is nothing better than practice (and perseverance) to develop new skills. Try Harder, as Offensive Security says.