Hello again!
I am a Finn and Finnish is my native language, I read a lot, and I can’t get around reading the Kalevala
The language is just so old-fashioned and difficult, an I swear Mr Lönnrot made up some of the words to make the meter work! Actually I just recently acquired a book that is the Kalevala story written in prose and in (reasonably) contemporary Finnish. I should get to reading that. Anyways, I wanted to say your goal is very ambitious!
Reading the same book in both Finnish and English is a good idea! The Finnish translations of both Harry Potter and the Hobbit are high quality. You'll be learning some vocabulary that doesn’t necessarily have practical everyday use, but that is merely a bonus!
The language board has been a bit quiet lately, but let’s hope others will join in too!