Nice work! Some general feedback:

• Your page title could be improved for SEO
• I'd add an FAQ section, e.g. what happens after 10k subs?
• Add some links to the header, e.g. jumping to pricing
• I'd have pricing higher up personally, or within the CTA in the header
• Your CTA of "Get started" is a tad weak IMO, could be better
• I really like the copy on the site, just a bit too wordy IMO, could be made more concise
• Missing a footer with the standard links, e.g. legals, email etc
• Signup page looks a bit sad at 1000px wide

To answer your questions:

Is it clear what the website offers?

Yep! Very clear, only improvement would be to make the copy more concise, to have a better CTA, and maybe a demo video of the set-up process.

Are there any features that are missing, yet crucial?

Nope!

Is the pricing reasonable?

Good, apart from the 10k limit. I'd also think about getting rid of the free plan, and instead showing what the product looks like via a demo video.