I like:
AnnaLeah KateMadelyn - I prefer
Madeleine and I despise the nickname
Maddie, though for some reason
Mattie doesn't grate my nerves as much, maybe it's the look and the fact it's MAT-ee and not MAD-ee
Alec AlexMatthias -
Matthew is a terrible twin name, it's practically the same name!
Blake
SamuelAbby and
Jacob - Not something I would use, but it's a huge step up from the others you've mentioned
EthanKatharine and
Alexander - Yay! I love
Katharine (this spelling!) and
Alexander compliments it very well