- Bellsprout was actually going to originally, just like Pinsir's it was cut; it would likely have related to Sprout Tower which just feels random to be based on Bellsprout.
- All of them have different roles. Arcanine is offensive (and Physical focused), Ninetales is defensive (and Special focused); Skuntank has more HP and hits harder, Purugly is faster; Primeape hits harder, Persian is faster. In this way they don't overshadow one another like Heracross does with Pinsir.
Arcanine is demonstrably way better, though. It's not like Oddish and Bellsprout where their final evolutions have equal BSTs. Arcanine has a BST 50 points ahead of Ninetales'. I definitely felt like I missed out by choosing LeafGreen (not least because Vulpix is in Hoenn).
And yet somehow, Magmortar comes out on top. It's consistently been a strong Pokemon in lower tiers thanks to its great power and coverage (it's not quite as expansive as Electivire, but it's one of the few Fire-types that learns Thunderbolt, and Focus Blast hits Rock-types hard), whereas Electivire consistently sucks shit, and its shiny new ability famously cursed it to rot in OU in its debut generation because people kept pairing it with Gyarados despite that being a terrible strategy.
I'm not saying "Motor Drive is a new ability in Gen IV, therefore it is automatically good" I'm just pointing out the disparity in Electivire getting a brand-new and conceptually somewhat-interesting ability while Magmortar is stuck with Flame Body which is fine but not that useful to it. I mean hell, Magmortar would definitely have benefited from a Motor Drive equivalent.