The only thing that would attract me to a "personal archive" product is being able to completely and totally own it. I want to have ownership not just over my data, but also of its presentation. If you decide you want to redesign the app and I hate it, then all of my previous time and energy is wasted.

This product immediately asserts, 'use me forever', but everything about the project says 'we raised money, and who knows how this will play out.' It always frustrates me that companies are willing to gloss over that obvious conflict when entering in to such a potentially long commitment with their users.

I don't mean to be overtly negative, but instead just want to point out something you may have overlooked. I would expect that you want to attract users who don't take these choices lightly, right?