Hey,
There seem to be a lot of mixed opinions out there in the hobby...
Some people will talk about 'aggressive' snakes, and others will tell you that there is no such thing as an aggressive snake; that they are simply reacting to environmental triggers, and that it is defensive.
My first snake was a coastal. I got him at 6 months old, and have had him ever since. He has never bitten / never even struck, despite all of the nerves and uncertainty that goes with owning your first snake!
Next I got a pair of Darwin Carpets, about 8 months old at the time. The male is the most placid snake I've ever seen (has never bitten/struck just like the coastal, but seems extremely comfortable with handling) and the female is a terror! In the enclosure, out of the enclosure, on the floor, in the hand... a terror! She has improved dramatically with size and handling. She still coils in preparation for strike when I go near the enclosure... You almost have to fool her into forgetting she's being handled... With hook handling, a lot of patience, and gradual introduction to free handling, she is at the point where I can handle her out of the enclosure... but I don't even think about it inside the enclosure... and she's very jumpy when first touched by the hook.
I also have a six year old pair of Darwins... The male is about 5 kilo (he's on a bit of a diet also) and is an impressive sight! He has such a placid temperament, and the female is fairly similair, just a bit flighty.
The challenge is... when they're small, you can cop a bunch of bites and chalk it up to 'conditioning.' When they are the size you're dealing with... it's preferable to avoid those bites! They might have to become 'look don't touch' specimens if they don't snap out of it... and JMO, but I think an enclosure of Medusa's size is too small for her size... I think she should be in something at least 1800 x 600 x 600... Again, just my opinion.