Default Not able to uninstall system apps using titanium or root toolbox

Hi i just installed paranoid latest 4.4 rc1(converted to all-f2fs) using twrp 2.7.1.1.
i am surprised
what i found is the system apps are not uninstalling. both titanium backup and toolbox are saying successfull uninstall but they are not..!!
is there any problem with all-f2fs partitions..??

Nexus 7 32gb wifi (GROUPER)
twrp 2.7.1.1
paranoid 4.4 rc1 ( Converted to f2fs ROM ).
Pa-gapps-mini-module.

and i cant flash stock gapp and full gapps which are above 220MB i can understand that f2fs file system will take more storage than normal ext4. so i flashed mini module.
is there any way i can increase /system partition..??