This is mentioned elsewhere, but I wanted to get it on the wish list. It would be very helpful to integrate DT Register with DT Billing, naturally through Community Builder. When a person registers, they should have the option (if allowed per event) of paying the entire amount or designating a payment/deposit. They should then be able to log back on at a later time and make additional payments.
This would be great for my site! I'm having to hack deposits with custom fields and it barely works. My bookkeeper would love me forever if we had multiple payments. She wouldn't have to follow up with each registrant to make payment arrangements.