>>31315469>most iconic charactersWell sure, it was the first game and established several recurring character archetypes. It helps that most of the notable character have shown up in at least four games since then.
>most iconic citiesI admit out of all the regions I'm only confident I could look at the map and name all the cities in Kanto and Johto, but again, that's mostly thanks to the imprinted nostalgia and seeing them so often.
Everyone remembers Pallet Town, but it's not particularly noteworthy compared to the other starting towns aside from the fact that it was the first and three of the most well-known and appreciated characters in the franchise lived there.
Saffron is totally barren compared to later hub cities. Even using Celadon for comparison, it's outshone by Goldenrod just one gen later.
Aside from Lavender Town, Cinnabar Island and Fuschia City, most of Kanto's towns don't really stand out.
>a good regional PokédexHalf the dex is either Poison, Water or Normal type.
There is ONE Ghost and Dragon line. There are only two Ice types that aren't unique encounters.
Speaking of unique Pokémon, Kanto probably has proportionally more than any other region. Aside from the four Legendaries, there are several Pokémon you can only get from in-game trades like Farfetch'd, Jynx, Lickitung (until Yellow) and Mr. Mime. Eevee, Lapras and one of the Hitmons are gifts, along with one of the Fossils. Kanto is the only region without a breeding Day-Care, so you're stuck with what you get unless you've got some generous friends to trade with. If I remember correctly, you can only get around 120 of the 150 obtainable Pokémon in a single cart without trading. That's around 20% of the regional dex missing in any given run.
I'd rate it a pretty mediocre dex overall. The Pokémon are mostly at least decent but it suffers pretty badly in diversity and availability. Better than DP Sinnoh and Alola but it leaves a lot to be desired.