Anything and everything pertaining to Walter will depend on how well the movie does. While Lola Bunny was used in every Looney Tunes project since Space Jam, the little aliens haven't been seen since. And Lola's only there to balance out the lack of female characters. Even then, her biggest roles were in the crappy generic Looney Tunes Babies and the crappy generic Loonatics. She plays a semi-major recurring role in the new show, but she's not on every episode... before that, she had one internet quality Looney Tunes cartoon to herself and was a minor character in Tweety;s High Flying adventure.
As for Muppet movie characters... other than Polly and Clueless being used in a UK exclusive Muppets Tonight short, they haven't exactly added any movie characters before. Sure, you may see someone reused for a crowd scene...