Given the nature of students doing Latin, in theory I think it's just as hard to get 30 in Latin as it would be to get 45+ in any other subject. I have a friend who is doing Latin next year (same as me), this year he got 50 for both Methods and Accounting.
As appianway said, different subjects are difficult for different reasons. Latin's not really conceptually hard, it's the fact that students doing it are very bright - which makes it harder to score well. No student in the state can get 50 for Latin (raw or scaled), since there are not enough students in the state who do it to get the proper "bell curve".
EDIT: The +17 increase illustrates that getting 30 is in no way easy - even getting mid 30's for Latin is very good. Anything above 40 raw for a LOTE like Latin is incredible - hence, you don't see that many names for Latin in the newspaper.
If want a score in any subject, you have to work hard and put in the effort. I myself haven't started any Aeneid I, but I plan to soon. xD