I want to limit the number of fields I present to users (such as removing address/ZIP/phone) but we'll needs those fields for direct mail. Our sales team still needs to fix process for converting contacts/leads.
Does it make sense to have users set up account and then follow up with another email/screen where users set up e-mail preferences and they are prompted to provide additional information?
Why limit the number of fields so heavily? Are your analytics showing really bad process abandonment or dropoff within the page flow?
If your new users are expecting to eventually receive mail or phone calls from your organization, it won't put them off to provide an address and phone number (many of them likely have autofill browser capabilities anyway) in addition to their username and email address. If they aren't, I'd be more concerned about how they'd react when they get undesirable mail/phone calls than about them initially abandoning the registration process.
While it does makes sense, must people would skip it. (I'm taking my behavior as source). If you really need those fields filled, either put them or give them a reason to fill them up.
For example, let them register with the minimum number of fields, send an activation e-mail that led your customers to those new fields. You must sell the idea as why they need to fill the fields. To improve, ask for the zip code and get a web service to look-up the address, leaving the customer to fill only the house number and complement. It is very common where I live (Brazil) and when this option is offered I do fill every field.
I don't know about your business, but let people know that they are being rewarded in some sort of way by filling every field.
