Ampharos's two earlier stages are so much better than the final. :P
On that note, Eevee is the best Pokemon of all time ever, with Umbreon being the best evo. My darling one from Crystal knew Return, and kicked so much bum with it, because it adored me so. Jirachi is a close second from sheer adorable-ness.
I'm not really sure of the best non-cheating method to get Jirachi though. :/