I'm currently grinding for my fight against Elesa since my whole team is a bit underleveled.
Servine (Venix) Lv22
Growlithe (Vice) Lv23
I'm planning on switching Magnemite with either my Herdier Lv21 or my Delcatty Lv18 for the battle with Elesa. I'm also trying to get Eevee to evolve either into Espeon or Umbreon soon. I'm leaning towards Umbreon since I prefer it. I did find a Thunderstone in Nimbasa City, but I already have a Jolteon on White that I plan to transfer once I'm done with the main game. Running around in the grass for Riolu and Eevee was totally worth it. I also found a level 25 Braviary on the way to Nimbasa that will become my main flying Pokemon. The game is going good so far.