I think having a W/L record would be a nice feature to have. Pretty much all video games these days have a W/L stat some where. It doesn't have to be a competitive feature unless you make it that way. If someone wants to have a 200/0 W/L because they battle the same person, battle someone with Pokemon 50 lvl's below theirs, or battle outside of a Tier doesn't mean they are actually good.
My suggestion would be if a W/L is added into the game it should be broken up into groups.
1. There should be a general W/L
2. Each type of battle should have it own W/L. (Friendlies, Tourney Modes, etc…)
3. The Battle Tower, Matchmaking.
4. Official Tournys should get there own special recognition.
Tourney mode should have the Tiers built in. Like when selecting tourney mode you can pick either OU, UU, or NU. When you pick a tier the following rules will apply (Banned Pokemon, Moves, etc…). Each tier should have its own W/L.
For official tourney's the winner should get a special recognition in some way. I was thinking, and which I think it had been suggested before is that the W/L and special recognition should be on the back of your trainer card. Which you can have an option when you right click a player you have the ability to view their card. Which then you can view their W/L records and Tourney wins.
These are just my thoughts it would just be a nice feature to have around. Specially for the players that will be here for a long time to come.