Ledger Joker has been done to death. It was overkill by the last release. It would actually be like a 4.0, they've done so many. You say it's overkill when Leto Joker only has one preorder solicited figure so far, but want what would be the 6th Ledger figue by them.
Hot Toys has done enough Bale Batman figures. They wouldn't even improve the Begins Batman or do it the right way. They'd still make an inaccurate one piece rubber suit and, if the Armory Batman is any indication, a repaint of the old Original Costume/Toy Fairs parts. They don't care enough to actually improve it and the differences would be negligible.
The 2009 Dent was a dud and sold poorly. The character's hype was short lived and nobody cares about him anymore.
I'd love a Ra's al Ghul to complete the line, but that ship has sailed.
Time to let the Nolan crap go. It had it's day with collectibles and it was a fun 6 to 7 years of solid Hot Toys releases. If people weren't happy with Hot Toys' offerings then, there's a good chance they wouldn't be satisfied with redos or whatever Hot Toys would do now. They've peaked, they've plateaued. Things like the Armory, Bank Robber 2.0 and signal set are proof of this. The Dark Knight trilogy had it's time in the toy and collectible spotlight.