Alex Kapranos has responded to fans question about follow up albums with "No more FFS for me, thanks. Time to write a new FF LP."
When Nick McCarthy left the group and people asked whether he has left FFS as well. Alex responded "I think everyone is out of FFS"
If I divide Sparks into era
Rock band era - Debut album Sparks to Introducing Sparks
Synth Pop - No. 1 in Heaven to Balls
Pop Minimalist - Lil' Beethoven to Ingmar Bergman
The current era is the synthesis/encapsulation era which I believe started with FFS and last to today. I think from FFS onwards Sparks are now definitely a rock band again where previously you could argue they haven't been a rock group outside isolated songs since perhaps Angst In the Pants.
Sparks Hippopotamus is probably the quintessential Sparks album if you don't consider FFS to be a pure Sparks album due to its collaboration status.