Ensuring a short-term "win" for the user (perhaps by breaking up the on-boarding into small enough parts to ensure at least 1 part of it is "completed" vs. requiring the entire thing to be done (all or nothing) could engage more users.
You might see more users complete the whole process, as well as become "active" users of product, if they are able to complete a part of it more easily...
It's about finding a good balance. Too difficult and people give up. Too easy and people don't invest into the product. I think a similar thing applies to free vs paid. Some times paid is better because free can be treated as cheap or with little value.