Hey Hobbes, I think maybe I remember you from the AGS forums a looong time ago (I was posting as Duzz).
From the sounds of it, PowerQuest would suit you. It does do the things you want, while trying to be simple to use like AGS is.
But unity *is* a lot more complicated than AGS, there's no getting around that, because it's made to be able to do any type of game. There's a gazillion buttons and options everywhere. Most of it you just ignore, and PowerQuest tries to simplify things so that you can more or less work the same as in AGS. But all the extra complexity is still there. Things like light effects, you'll have to learn about how to use those systems in unity. It can be easy to break something and be unsure what. So that's the downside.
Scripting in PowerQuest should be as easy as with AGS. I don't think that'll be a problem for you. And if you've been scripting in AGS then I wouldn't say you have zero programming skills ;) AGS is basically a 'C style' language and C# pretty much the same thing (if anything, it's meant to be easier).
Another disadvantage is that there's not a long history of people using PowerQuest like there is for AGS, so there's no forums to trawl through to find answers, you'll have to ask them yourself. The discord is more active than these forums, but feel free to use either.
Hope that helps! :)