Hi, here's a question for you
Suppose that you have an interesting scholarship, meaning that you don't need funding (at all) from your PhD advisor.
When you applied for this scholarship, you had to present a project. However, you have the possibility to choose a different project for your thesis, upon approval. Your advisor/professors told you it's ok to choose a different subject, so you really are not tied to it.
The project you presented is interesting, data is already collected and ready to use.
On the other hand, you have some other project in mind, but you would have to start from zero.
What would you choose, considering that money is not involved in the equation ?
A. The easy project that you are not so "passionated" about but that could "easily" get done.
B. The second project, that would need more work but is more interesting and challenging (in a positive way).