R1 TK and FO TK are very different, it's ok to love both for what they are, I know I do.
Both sets of armour are also vastly different and each has it's own differing construction methods and intricacies so their is a lot to like.
Maybe start off with what captured your imagination first, work through that and once done and you become an approved 501st member, then focus on the next project.
Like many once you have completed one, you will most certainly be looking for another to get cracking on.
Welcome aboard Michael.