No-frills builder for landing pages?

Hey all,

Does anyone know of a site builder that's super simple to use to build landing pages? I've tried a lot of the solutions out there and I feel very disappointed. They either have templates that are too "creative" or straight out of the 90's, and most are bloated with features and just too many ways to make tweaks which makes customizing templates pretty hard (and starting from scratch even harder).

What I want is:

simple, modern-looking templates to get started
ability to drag and drop blocks with elements like headers, heros, testimonials, pricing...
ability to edit text and images from pre-made blocks (bonus: connect to free illustration sites to easily insert their images)
ability to set a simple theme (font and color scheme), and have all blocks be updated at once
export as HTML+CSS

And that's it! All I want is to build a quick, professional-looking landing page for my product.

Along those lines I found https://www.launchaco.com, but while the editor is very easy to use and the output is clean, it doesn't feel super professional. The blocks might benefit from "more design".

Cheers,