If you choose to be reborn, you will not have magic powers, but you will unlock a status window and a skill tree that you can use to give yourself new skills and abilities and improve your physical characteristics.
You’ll get the same thing if you choose to be reincarnated, however, magic will be a factor. And the age of the world will be somewhere like 50-ish years before the full rollout of the industrial revolution, technology-wise. (minor clarification, you keep your current knowledge either way)
However, you will not be the hero or the chosen one. You’re just going to be a person with a perk.
If you take the magic route, you are guaranteed magical ability of at least C tier rank, and since you have the status window, you will be able to upgrade that through patient and dedicated practice.
I did not see the changes you made to premise. But I would still stay with modern comforts and lack of terrible diseases.