>>56129353I'd say Norman shows off how normal types are often the wild cards that get a lot of gimmicks slapped on them. Main evidence towards this being Slaking and possibly Spinda, though it sucks gen 3 also had Kecleon and Castform and Norman doesn't use either of them. But I think the idea is still there and just poorly implemented due to his gym teaching all about specific battle techniques and focuses.
I'd give Lenora the "early route normal types" descriptor you originally gave Norman, with the twist of demonstrating how an early route shitmon who reaches their final form extremely early on can be devastating to a player's early game team of mostly unevolved Pokemon. Watchog can really fuck up your day with Retaliate.
I think the purpose of Cheren in BW2 is to specialize in the most neutral possible type to downplay the potential complexity of type matchups, basically the exact opposite of Cilan/Chili/Cress in BW1 who were extremely hamfisted in their attempt to tutorialize basic type matchups. Without many weaknesses to exploit, the fight against Cheren is basically a slugfest where you want to win as quickly as possible before Lillipup can set up too many Work Ups, which incentivizes brute offense as opposed to switching in the correct Pokemon to resist the ace.
There's not much to say about Whitney and Larry though. I think you're right about them. Had Norman gone all-in with the gimmickmon concept, I would have called him the best normal type user. Lenora definitely scares me the most out of all of them (unless I choose Tepig), and I think she does the best job of showing how normal types can peak really early on and how reliable a good neutral STAB can be.