This is good advice for Ancient Greek for the most part, although you would need to adjust your approach depending on the dialect you plan to study. Given its central place in the Greek canon, I've always advised starting with Homeric Greek. I would never advise starting with koine, even if you only plan to read the New Testament. It's limiting you to language only complicated enough to write a travel brochure (καὶ εὐθὺς ἀναβαίνων...), when you could be reading Greek in all of its beauty and complexity.
So what I would advise learning by rote is:
* The three noun declensions
* The present, imperfect, first and second aorist, perfect, and future indicative of regular verbs
* The active present optative, subjunctive, and imperative of regular verbs
* The full paradigms of εἰμί and φημί
From there, I'd pick up Owen and Goodspeed's Homeric Vocabularies and a good, generously annotated (but not translated) edition of the Iliad. Pharr's Homeric Greek could also help with a few forms like the dual that are important to be able to recognize, but far from necessary to memorize.
So what I would advise learning by rote is:
* The three noun declensions
* The present, imperfect, first and second aorist, perfect, and future indicative of regular verbs
* The active present optative, subjunctive, and imperative of regular verbs
* The full paradigms of εἰμί and φημί
From there, I'd pick up Owen and Goodspeed's Homeric Vocabularies and a good, generously annotated (but not translated) edition of the Iliad. Pharr's Homeric Greek could also help with a few forms like the dual that are important to be able to recognize, but far from necessary to memorize.
e: Comment formatting.