If people can say why they love Batman or the amount of Bat people or even ask for more (Freeze/Ivy) then why can't I say why I don't? Does it annoy people? I'm annoyed by people that don't like Superman just because he's "too powerful" or some other inane reason but I never go "well you can't change it so stfu", I say why I think they're wrong or debate with them.
I agree with you on the most part, but ...
Imagine Cashcom would create a pure Marvel brawler with ... let's say ... 40 characters total, out of which 20 should be heroes and 20 should be villains.
In my eyes Marvel has much better (characters overall actually) villains than DC, but even in Marvel there is one hero who simply stands out with his rogue gallery. Who is it? Spider-Man of course.
I personally wouldn't mind having a lot of Spider-Man rogues in the game, simply because they're so fancy and versatile. They would be a great addition for the game, even though many others would fall shortly. Spider-Man simply has the best rogue gallery out of all comic book superheroes.
What about Batman?
When it comes to DC I would say that he is the one with the best rogue gallery. Obviously others have great rogue galleries as well like Flash and Superman (actually only these two), but Batman has sooo many villains and there are some really good ones.
Is it a good call that we get Joker AND Harley Quinn (I love Harley Quinn), Nightwing (I love him too) AND Catwoman AND Bane, who are all ... basically mostly gadget characters? No, that's not cool and it should be obvious that they're only there so that WB and DC can make more money, because of the movies and stuff like that.
You're right about that part.
But Batman characters wouldn't have been a bad call, if they came up with the really good characters who would offer you an unique playstyle. Yes, you can make the Joker feel and play differently than Harley Quinn and I'm sure that NRS can pull that off as easy as Crapcom did with with Hulk and She-Hulk, Wolverine and X-23 and so on, but ...
... wouldn't it be better to come up with characters who have unique powers and grant you the chance to play with an entirely new power set? Characters like Poison Ivy, Clayface and Scarecrow! They have much more to offer than Catwoman and Bane.
It's not about having too many Batman characters. The bigger problem is that NRS doesn't bring out the best out of the Batman universe.
(Unfortunately if we're honest ... Poison Ivy, Clayface and Scarecrow are basically the only Batman villains who would offer you something unique ... all of his other rogues are only psychopaths with guns and gagdets and while some of them are cool, none of them are talk-worthy. I left Mr. Freeze out because of Captain Cold)