Heh, the thing about Serperior is that the only decent Serperiors are from the Dream World. The starter variants are sub-par when compared to the other grass types obtainable in Black/White, which is why I replaced mine with Liligant the first time the opportunity came up.
As for my own failed plans, I wanted to slap a Klinklang onto my end-game team, and even managed to train up a Klang, but their barren movepool consisting of Rock Smash, 85% accuracy Steel Move, and Return made using them in battle difficult, and I could never find the time to level them up to the point of gaining Gear Charge, so when endgame came up, I took my Serperior out of the daycare and decided to use that in place of Klang.
If I had learned the daycare exploit earlier however, I could have gotten a Gear Charge Klinklang at exactly level 50 (which is what I did post-game).