It's not about unlocking everything for me. Even with a second playthrough you're probably far from seeing everything. Sure, the main storyline somewhat repeats itself, but there are multiple companion side stories and all kinds of other stuff you can stumble upon by accident that you then incorporate into your playthrough.

This is probably one of the best games for you to just enjoy, because you can still continue when failing something (unless your party is completely wiped, but fights aren't really that hard in easy and normal difficulties). It's a pretty personalized experience.