Cummings' long game is that he thinks the country should be run by a small group of very clever people, and that he is one of them.
He thinks the small group should get to choose a token prime minister to follow their bidding. Said so in the interview.
He does not think the small group need to be democratically elected. Clearly he finds democratic mechanisms to be useful tools to exploit occasionally, but he doesn't support the concept of democracy.
And I'm pretty sure he's being deliberately vague as well as genuinely poor at communicating.
The reasons for his opacity being:
a) mostly he doesn't have a detailed plan of what he wants to build, just what he wants to tear down. After all, now that his wondrousness is here, he'll be able to create whatever's wanted in his kitchen with a small aubergine;
and
(b) where he does have a detailed plan, he knows it's completely unacceptable to the general public. His repeated flirting with eugenicists, for example, hints at what might be under the covers.
And yes, he's bewitched by technology, and believes more science always => better outcomes. And higher IQ always => better things.
These are beliefs which a cursory glance at history would knock on the head (mechanised slaughter of WWI; Holocaust's use of tech; nuclear weapons...).
Technology allows humans to pursue the sorts of aims that humans have always pursued: but faster, more effectively and reaching more people. So if they want to find a vaccine for a new virus, technology will help. If they want to install a dictator, sexually abuse children, deploy a weapon, or trigger a genocide in Burma or a lynch mob to attack the US Capitol, technology will help. Humans remain the same saints and sinners they've always been.
This is something people dazzled by technology often forget.