There are many ways to make a setup. I did think about it quite some time, did research on what file systems to use where... did consider whether to use encryption-->lvm or lvm-->encryption.

After carefull consideration I just came to the conclusion that I prefer this setup more. I do want to have independant root and only the actualy data on the lvm. Hence I chose that approach.

There's no right/wrong here. Just think of the consequences of your choices and what suits you the most.