Ask HN: Advice, books, blogs etc. for a CTO of a young SAAS startup?

Background: 1 year old startup, co-founded while in college, joined it full-time 3 months back (when I graduated), have a product and paid users, currently focused on growing our user base.

I have found a lot of material (books, blogs, videos) on starting/running startups but nothing I have seen or read tells much about how to lead the tech team or what a tech team should be doing early on.

I am plagued by so many questions: How should I split my time between bugs, features and refactors? For any month, what should my targets be? How to estimate the time to fix a bug/release a feature? Is it ok to work on something that may not bring in more revenue in the near future?

Or maybe I am asking the wrong questions altogether. Please guide.