_DilLen
Why leave it aside? The MC doesn't need a single pokemon, it can have several, I don't see the need to discard it especially because they have a good potential so as long as they don't face the strongest pokemon in their last stages, it's going to be useful, especially if it gets to mega evolve it, besides it's giant and if it grows more and mega evolves and grows even more, it's a perfect imitation of a fighter so it will always serve for transportation and other things.
Keep Beedrill because I want a rivalry to form between Zubat and Beedrill, Zubat wanting to become a strong Crobat and keeping all of Gray’s attention on him while Beedrill wanting to become strong enough to show Gray he isn’t useless and proving himself to Gray, plus before in the FF there was a way to permanently Mega Evolve a Pokemon, A Permanent Mega Beedrill should be very useful to Gray👍