If you play on an emu, you can savestate to keep multiple runs going at once.
Not fond of Ekans at all, though obviously it can get things done with Dig just like anything. Wrap takes forever to KO anything and Ekans doesn't really get any good moves on its own. In fact, learning Dig is like the only thing it has going for it.
Also, since Karate Chop is normal in RBY, I believe you'd use Dig on a lot of things you'd use Low Kick on (eg Geodude). So it's more useful than just Poison/Electric things.
Yeah, Yellow Pikachu Thundershock is pretty borderline at KOing Pidgeys of similar levels, but your other mons at that point aren't doing any better at that point. It's definitely Mid tier at least.