‘Посадить в печку’ sounds good concerning animated objects like human beings.))) There’s even a proverb ‘Хоть горшком назови, только в печь не сажай’ ~Sticks and stones may break my bones (but words will never hurt me), which conveys the meaning somewhat tangential to that of Crocodile’s signature ‘Словом можно обидеть. Словарём – убить’))).

With regard to using 'печка' for СВЧ; in my book, you may easily use the word when you mention microwave ovens in small talk, etc.. People say that way more often than not in my hereabouts.

Overall, I’m impressed with your command of Russian. Great job. If you should decide to enhance your pronunciation even further , you may want to practice your Е a little bit more, in order that it won’t sound similar to ‘harsh’ Э in the word ‘это’in some of your phrases when it’s inappropriate (орэгами instead of оригами, птэродактель /птеродактель etc).