Phoebe had 2 Banette and 2 Dusclops
Glacia had 2 Glalie and 2 Sealeo
Drak had 2 Flygon
I get the complaints about gen 5 & 6 only having 4 pokemon normally for their e4, but at least they were all different.
Same applies to rs' leader rosters. Why did Flannery need 2 slugma? Norman, 2 slaking?
Though I guess in fairness its not like they had other options but that didn't stop Agatha & Lorelei from having things like gengar & slowbro. Why not give Glacia a castform for synergy with her hail stuff? Or Phoebe a Chimecho, its kinda ghostly and its from my pyre. Or just not have a ghost & ice e4 at all
With Flannery, the Camerupt line was seen as Team Magma's I think, so Slugma and Torkoal were the only viable candidates left.
Norman, 2 Slakings was pretty tough going, and I enjoyed the challenge but it did seem a bit unnecessary as the variety of choice as you say, and also that Slaking is supposed to be Norman's "signature Pokemon", having 2 sort of ruins the effect.
I don't mind the fact that Gym Leaders and Elite 4 Members having Pokemon that aren't of the right type, as long as they stuck with the flavour. but I understand Lorelei's Slowbro, and I do get Karen's Vileplume and Gengar too. Agatha was pushing it when all of her Pokemon were Poison anyway, Volkner's Ambipom and Flint's Steelix were outright ridiculous.
Phoebe only had Shedinja as an alternative, which is just gimmicky and not viable for an e4 candidate, Drake had Kingdra which he used in Emerald, but Glacia didn't have much choice to be honest. They perhaps should have thought a bit more about the used Dex, or the E4 types, but hey, I'm not a gamemaker and I don't know how their thought process was so I shouldn't be moaning (though it was quite an odd excision, as especially as every single one of those types had been in the E4 before then). I quite like the idea of a Phoebe having a Chimecho, especially when she has a few links to Mt Pyre as well. Which makes me wonder whether the E4 will get a bit of backstory and perhaps play a function in the game this time round?