I found this post on HN: https://www.ablg.io/blog/no-management-needed
The gist of it is "don't hire or appoint managers before ~20 engineers, it's just a distraction". I like the points, even if the "managers don't motivate people" line sounds controversial (it was in the HN comments.)
I agree with the premise not to hire full-time or even part-time managers at this point, and to have the founder/CTO do the minimum. In your early-stage startup you need every hire to have a strong internal drive and motivation, and a strong affinity for collaboration. Anyone who needs a manager to hold their hand or help them be part of the team won't be able to keep up, pivot or contribute effectively.
At this early stage too much management or process is waste. Yes, you're laying down culture and process debt that will need to be fixed later, but it's a waste trying to optimise prematurely to prevent it.
One side thing I've often observed is that people who thrive best without managers probably won't stick around once the management hierarchy comes in and they're expected to do 1-1s and performance reviews. Plan for their graceful exit.
Your founder/CTO can still screw up the management, especially if they haven't done it before. Get a coach or some very-part-time fractional support that won't distract or dilute the vision.