Not telling anyone what to do :-) but just pointing something out:
Not long ago, someone on this list helped me fix a recipe for blocking
large messages. As an aside, he suggested that the ten thousand char
limit I had was probably too small. I just peeked at the sizes of the
last 100 incoming. only four were over 6000 chars. Two of those were
spam, and one was quoting a spam to a "postmaster".
Of course, Your Mileage May Vary (especially if you get binaries as
attachments) but it looks like ten thou was a good limit for me after
all.