Something like these two lines should get you close to the answer you seek (not in Revit so I can’t test) and they should remove the Archi-Lab dependency which will save some headaches. It’s using the List.FilterByBoolMask node to filter the list.
floorPlans = List.FilterByBoolMask( views, views.GetParameterValueByName("Family") == "Floor Plan" )["in"];
ceilingPlans = List.FilterByBoolMask( views, views.GetParameterValueByName("Family") == "Ceiling Plan" )["in"];
Alternatively you can use an if statement to parse the content thusly (again, not tested so you might want to tweak it a bit):
floorPlans = List.Clean(views.GetParameterValueByName("Family") == "Floor Plan"? views: null, false );
ceilingPlans = List.Clean(views.GetParameterValueByName("Family") == "Ceiling Plan"? views: null, false );