Update on my progress.
Defeated Whitney, I had to train a bit before I did her, because my party had such a bad setup against her Milktank.
Scyther, Quilava, Pidgeotto for example, and Bellsprout and Mareep being slightly lower in level, so you can see why Rollout would own me.
But I got Scyther up to 22, it learned Wing Attack, and I proceeded to rape her with that.
Another thing that made the battle slightly harder was Attract and the Charm-thing, seeing as Scyther and Mareep were my only females.
Now I'm at Ecruteak City, on the way I have captured Sudowoodo, a Growlithe and I went and fixed my Eevee, but out of those, the latter is the only one I have strong plans for.
Growlithe was mostly to get an alternative for another Fire (if I ever need it), and Sudowoodo, because it's obvious for me to catch the "rares".
Next up will be training for the next gym, maybe watch out the burned tower, and all that.
Current party:
Quilava (level 22)
Scyther (level 22)
Pidgeotto (level 20)
Flaafy (level 20)
Bellsprout (level 20)
Eevee (level 5)