>>14
but 'ennen' and 'ilman' are prepositions. It's kinda like 'ago' is a postposition in English, not the dominant pattern, but still in there for some reason.
>>3
Grammatical case has nothing to do with tense. Also, case formations are pretty fucking regular in Finnish, and a lot of them aren't used that often. I'd say declension is more difficult in German, Latin, or Russian because it's less predictable for new words and there are multiple declension patterns. In Finnish there's only one.