Slovenia vs Croatia: been to Croatia, should I try Slovenia instead?

Did Split and Dubrovnik 3 years ago and loved Croatia. Now I have a week in September and friends keep telling me to do Slovenia instead of going back.

Is Slovenia actually different enough to feel like a new experience or is it going to feel like more of the same (gorgeous coastline, medieval towns, good seafood)? I know Ljubljana is supposed to be charming and Lake Bled is all over Instagram. But is there enough for a full week or would I run out of things to do after 4 days?

Also curious about the food. Croatian food was good but a bit repetitive after a week. Is Slovenian cuisine more varied?

Yes. Why not explore another country?