Yes I have experience running a company like this for more than 10 years.︀ I have only used a UK Ltd.
This is quite advantageous in EU and actually︁ in most countries.
The reason is, most DTA agreements include a non-discrimination clause which means︂ that a foreign company should not be treated worse than a local company. In a︃ lot of cases, complying to this means the country opts for LESS requirements on a︄ branch than on a local company. A reason for this is also that there are︅ lots of types of entities that don't necessarily fit 1:1 with the existing types of︆ entities in the jurisdiction. If we go back to the LLP case, if the LLP︇ doesn't exist locally, then through the DTA, it will have to be treated more lenient︈ in the various types of legislation, meaning it can avoid a lot of requirements. This︉ can be less requirements on paid-up share capital, less requirements on loans to/from the company,︊ less filing requirements etc. Because of all the DTA requirements, this can typically spill over︋ to UK Ltd companies.
I think your setup could work. It's not a setup I︌ have tried, but it is the sort of setup that I want to be able︍ to move to when needed.
Another advantage I see is that for a holding company,︎ using a UK Ltd is advantageous as it makes it possible to escape from a️ country and setting up business somewhere else without being stuck with a holding company in a jurisdiction you have no connection to anymore. By moving funds from a branch to the head office, and later maybe re-establishing the treaty non-resident status in another country, you have effectively re-domiciled your holding company without tearing down the whole structure.