Yeah, Neil's was pretty self-contained: it was really just a survey through the magic parts of the DCU. (which repurposed most of them for Vertigo) The series came reasonably later--this was still DC "special format," while the series came out once Vertigo was already well underway. I'm not sure if they had any definite future development of Tim in mind at the time--he was basically just the Guy Who Listens and Learns you need to provide a reason why everyone's talking about this stuff.
I will say this: I still maintain there are many elements of Tim that are suspiciously similar to the later Harry Potter. But I also imagine that even if there are Neil doesn't care to make a fuss.(and besides, it's not like he's hurting, and Tim isn't owned by him)