Q: What are the issues in changing to use an account in another country?

I’m looking to change from using an Netherlands (NL) registered Apple ID to a Thailand (TH) registered Apple ID. I left my native Netherlands a decade ago, and really would prefer to have everything charged to my Thai credit card, etc. I know that if I change the country on my Apple ID, I lose all the purchases. So instead, I am thinking I keep the NL account and start using the TH account.

iCloud - paid storage

I have an iCloud account tied to my NL account. I would probably clean it out and desert it, and just re-upload everything into an iCloud account which is tied to my TH account. This doesn’t seem to be a problem.

Apps - hundreds of euros spent

I think that on both my Mac and iOS devices I can simply change the App Store country and download applications from multiple accounts (& countries) onto the same device. My Mac could run applications purchased in my NL account as well as applications purchases in my TH account. No problem there either.

Movies, TV shows and music - not much money spent

When I switch my devices to using the TH account, the very few albums that I have purchased I guess will no longer be available. I don’t really care, I’ll either re-purchase them or just leave it be. Not a problem either.

Books - hundreds of euros spent

I have just tried to purchase a book on the Thai iBookstore. This works just fine, and iBooks on my Mac now shows the dozens of books I have on my NL account together with the book I ‘bought’ (it was a free book, but I don’t think that matters) on the TH store. It seems there is no real concern here.

What am I missing here? Yes, if I register my devices to the Thai account, then I will have to authenticate every time I want to download an app or book from my NL account. But once downloaded, I think I wont have to keep doing that. So, it doesn't seem too much of a hassle really?

One possible risk I see is that apps purchases on the NL account might only use iCloud store tied to an NL iCloud account? Does anyone have any experience in this?