I try to stick with my own ideas. It's worked once or twice (Acid Liability? Create an archetype? Too bad I completely sucked the one time I played it at a tournament, but I can tell you exactly why!) but my only City this season I went 1-4. Oh well.
Edit: And it's not because I "dislike archetypes" or anything like that... I still have my Metagross d playset, for example, and I have a Raieggs deck built. I just play what I enjoy playing, tournaments be damned. League wins are more important to me because that's what I can actually do most of the time... and I dominate my League... it hardly matters what I play.