I am assuming by splash screen your talking about the starting view?
You could filter out the starting view by:
starting_view_settings = FilteredElementCollector(doc).OfClass(StartingViewSettings).ToElements()
starting_view = doc.GetElement(starting_view_settings[0].ViewId)
all_views = FilteredElementCollector(doc).OfClass(clr.GetClrType(View)).ToElementIds()
for view in all_views:
if view != starting_view.Id:
try:
doc.Delete(view)
except:
pass