Yes, we agree regarding your first bullet-point regarding CFC rules, it was just the second bullet point I disagreed with
Just be careful not to bring "passport country" into the discussion, as it is completely irrelevant for anyone other than Eritrean and US citizens. What matters is residency, and if you no longer have residency in a country (even your "passport country") according to their internal rules, DTAs doesn't matter (as we both agree on). I am sure you know this, manu, but here's one example aiming to make this clear for other people reading this thread:
To not be considered a resident of your home country any more, certain rules obviously applies. Many countries consider you as a resident as long as your "center of economic interest" is still in the country. Other countries, such as my native Norway has a lot more complex, time-consuming rules for how to no longer be considered a tax resident according to internal rules. See this page in the PwC Tax Summary for Norway. The same site is very useful to quickly get an overview for your specific country of residence.
In the Norway example (click the PwC link for details), you have to prove tax residency in a different country, stay a maximum of 61 days per year in Norway and not have a dwelling at your disposal in the country. For people that has been residents (not citizens) of Norway for more than 10 years, the above criterion has to be fulfilled for 3 whole calendar years before you are no longer considered a "resident for tax purposes." But once you are no longer considered a resident, you no longer need to prove residence elsewhere. Your tax obligation to your "home country" is now ZERO as long as you don't have income sourced in the country, business operating there or spend a significant amount of time there (basically re-establishing tax residency).
Sorry for the lengthy example, my point is only that the term "passport country" is irrelevant in this discussion for non-US/Eritrean citizens.
...on distributed profits. Which can be an interesting mechanism for a growing business (and is a lot less than in many western countries). Although I have not looked into the rules for travel expenses for Estonia, I would think the tax code would allow the company to pay for quite a few travel expenses (tax free) for the average (long-term) digital nomad, reducing the overall effective tax rate. Although I am not sure how this would work as a resident of nowhere, as tax free travel expenses typically applies when you are away from your home.
The main benefit of the e-residency, however, is that as a small business owner with a simple setup can do most of your government reporting online without paying others to do it for you. It basically just simplifies the day to day reporting and managing of the business and lowers the costs you have to spend paying third parties to handle this for you. If that makes sense or not depends on your individual circumstances, obviously.