My suggestion would be leaning towards the simplification of the process. Require only very basic data (i.e. email) and let the user to have a great first experience with your product without unnecessary friction. (I strongly recommend FB or Google signup makes it one-step process and you get much more than just an email.)
To build the quality of your user database, you can ask for more details later. It's always a good practice to offer something in exchange, i.e. if user has 100% profile completion you benefit them with premium feature for certain period of time. Engaged users will take action. Not-engaged users will at least look good on paper and perhaps tells you more about your acquisition activities. If acquisition part of the product funnel works, then shift your focus to on-boarding and retention.
I don't want to say that capturing more data at the beginning and maintaining quality is not a goof approach. But it's likely to require more marketing efforts (both time and money) and that is a showstopper for many startups. But if have other channels how you drive the traffic and the brand is already established, than it may work.

I hope this answer will help you. Let me know what decision you have made.
Also, please feel free to reach out.

Regards,
Filip