I'm seven badges into the game right now, taking out Team Rocket in Goldenrod. So far, none of the gyms have been all that difficult, to be honest.
Falkner was taken out by a Geodude that I had picked up on Route 46. Honestly, the Pidgeotto was a disappointment, since it no longer had Mud-Slap to beat down those Mareep and Geodude that were coming after it.
Bugsy was assassinated by a Spearow and a Geodude, although Scyther's STAB U-Turn did manage a critical hit to KO my Geodude, which I pretty much hated.
Whitney was a lot easier than I expected her to be, due to the fact that my Aipom's combination of Tickle and Headbutt basically slaughtered her Miltank. The Clefairy did Metronome a Stone Edge to OHKO my Scyther. Poor guy.
Morty was the most challenging for me so far. My Kadabra managed to get it down to a sliver of health after a Psybeam, but it one-hit KO'ed my Kadabra with a Shadow Ball, and then he healed it up with a Super Potion. My Aipom once again came through for me, Tickling it a couple times, and then two-hitting it with Astonish.
Chuck was destroyed by Kadabra. And I mean destroyed. Psybeam one-hitted Primeape, and two-hitted Poliwrath.
Jasmine was kind of difficult, but my Ambipom actually managed to get the kill, this time with a Technician-boosted Double Hit when Steelix was at low health. Man, I love Ambipom.
Pryce went down to Ambipom's Double Hit and Alakazam's Focus Blast. Easy as pie.