Since you are reading here Rich Harris; while I really admire your solutions, one weak point with Svelte seems to be a clear unit testing solution, or at least docs last I looked. I also noticed this with Ractive, and feel it weakens these in the eyes of many businesses considering these tools. I know it's a solved/solvable problem but it feels like better docs and samples in quick start guides would help.
I admire Rich Harris' work as well. 4 years ago I was picking my first SPA framework. Narrowed it down to Ractive and Vue. Picked ractive, it had a beautiful documentation and tutorial. Still have an app in production based on ractive. But author abandoned it. Then vue 2 took off. I didn't have a choice but switch. Recently I started playing with Svelte/Sapper again. I like it a bit better than vue for some reason an…
To be clear though, Ractive is still under development by other maintainers: https://github.com/RactiveJS/Ractive.
> he should narrow his focus
Not to speak for him, but I think Rich is an "idea guy" and we'd all miss out if he were throttled to just one thing :-)