I am not looking for a viable setup
I am out of those games and keep my situation very simple (and effective).
Taxation is something every founder should be involved in at all times. I cant remember how much we saved. It's your plan, you know how to execute. Only hire external help when its absolutely necessary. Not in the last to avoid your data ending up in the wrong hands. Corporate structures cant be protected by IP for instance.
Accounting, when compartmentalised per country, can be outsourced. I do agree on that wrt freeing up time. Group accounting etc should be done in house. Else its literally your advantage on the streets for your competition. Not directly, but indirectly. With that I mean that if you involve too many external parties and they see that you are on to something with how your setup works, they will copy and paste that to your competition.
Be careful about what you outsource for that matter.