You make an interesting point (or rant of you prefer), however, I see a few differences between Vaporeon and Alomomola.
1) Vaporeon has better options in terms of both supporting a team and going on the offensive. Scald is a valuable tool and Vaporeon's SpA is simply higher. Not to mention the fact that it can attack grass, flying, dragon, and ground types with ice beam. Plus, the addition of roar makes it a useful phaser if necessary. A role that Alomomola cannot fulfill.
2) Consider the number of roles Vaporeon can play. It can be a healer, a staler, an offensive and defensive threat eliminator (burn lowering attack, toxic killing walls), and even a baton passer. Alomomola can't perform this many jobs so well.
Vaporeon is the superior Pokemon, and this isn't even including its wonderful Dream World Ability, Hydration.
"I feel like I got hit with a Dracula, by King Kong." -BMO