Random ranked PvP battles need an option to avoid being matched against guildmates.
I haven't memorized the nicknames of even half of my guild, so it's hard to know if I'm battling a guildmate or not.
Another suggestion would be the option to avoid battling the same opponent twice in a row.
The last suggestion would be to improve the selection of random teams.
It's really bad, for example, when you have 3 grass-type Pokémon and 2 bug-type Pokémon, and your opponent has Charizard, Ho-Oh and End of Battle.