Sorry for a year-long hiatus, been busy doing other stuff, even stepped away from the bass completely for almost two months... Got back to it though, unavoidably, and in order to maximize the effects of my practice routine asked myself "what do I need to focus on in order to develop the ear-to-fretboard connection as much as possible, along with technique"? Looked back at my practice diaries from "times yonder" and figured out that dedicating the largest portion of my time available to the study of chord tones seems to be most promising.
Why? Well, because seeing how harmony lays out on the fingerboard offers sort of a clear GPS guide to getting where you need to be in the musical context, and in a way that makes it helpful and comprehensible for other musicians in the band, as well as the listeners, too. Add solid rhythmic feel and phrasing to it, and you are pretty much there when it comes to creating functional and convincing bass lines. Therefore, I will point to several good resources for those who would like to embark on this quintessential field of study.
To begin with, it only made sense to me to follow the method (even if it is an older book) of a man who has long been championing the advantages of focusing on chord tones rather than scales and sheer technical exercises devoid of musical content - the one and only Jeff Berlin! He has been preaching very strong views on the state of music education, especially in the domain of teaching/learning electric bass in modern music, for decades, and some 35 years ago came up with a manual intended to show in practice how his philosophy of learning should be applied in practice. The book is long out of print, but here it is as available online: