Danger, Will Robinson!
I followed a similar path to the one you now tread. I cofounded, and managed/grew the dev team from me to forty folks.
Three years ago (after seven years of just "tech director"), I took the mantle of CTO.
Error.
CTO is not a technical role. To do it well, you must be technical, but it is in reality a sales and marketing role, both internal and external. I found myself isolated from our tech team in short order, as as CTO one is the public and board level technical face of the company - and that becomes all consuming, and you become the perceived source of all the problems. You become the messenger, who is much shot at, by both clients and your former allies in your technical team. The clients shout at you for bugs. The developers shout at you for pleading that bugs get fixed. You become that which lives between hammer and anvil. You are no longer part of the team. You are the boss.
So - unless you want to get out of technology and want to work as a marketeer/apology bot, don't aim for CTO. I did, it broke me.
I left my company today, as I started it for the love of tech, and making cool stuff - and at the point of organisational development they have reached, that is not something there's any scope for a CTO to do.
Lesson learned.