I hope they are as they appear to be a good counterpoint to the evil teams, I have no problem with being "generic" as the light is good trope is one of my favorite tropes.
On Oak's cousin I don't get why they made him when they could of just of used the good old Prof. Oak instead, its not like he hasn't cameoed in other games before.
As for my thoughts on the Alohan variants while I do like the new Raichu, Sandslash, and Ninetails their in universe reason for their inclusion doesn't make sense. Why haven't other species adapted in other regions? How the hell does a Sandshrew adapt to a climate that would kill it? The Dark type isn't really about actual darkness so how does it fit in with Raticate becoming nocturnal? I probably overthinking it.