I just moved from a Phantom to a Tarot 650 and like you, Pumpkinguy, I loved learning all the different aspects of design and deciding on what I wanted. I must say that it was a very demanding task since the trade-space is so huge, but as I started to nail down one decision after another I was really pleased with the way it all came together.
BUT, and this is a really big but: I had a very specific set of goals. I flew with the Phantom long enough to understand exactly where it had weaknesses for my very specific AP needs and I was able to define a set of concrete requirements for my new build. I can't imagine how you make all the decisions that need to be made unless you are driving to a clearly quantified goal.
My advise is to really sit and think about what you need rather than going into this with a generic goal of "building something bigger." What kind of payload will you carry? What kind of filming are you going to do? What kind of functionality will you need from your FC? What kind of flight times are you shooting for? What about portability? Etc. etc. If you don't have those answers then to be honest I would wait a bit: wait till you understand the problems you have with your current setup and seek to solve those rather than upgrading for the sake of it.