This is a hard one to answer, Sheila wanted me to answer.
If you asked me which of our snakes I would cry the most if they died, it would be a toss up between Elvira (12' Albino Burm) and Timber (Northern Pinesnake).
Those are our definite best educational snakes - and the ones I feel I "know" the best, and know me the best. Unfortunately Timber is 14 years old (Northern Pinesnake) and I'm sure nature will one day take it's course - and he will be gone.
Favorite snake species that I can think of while stitting here are burms (for their gentle nature), Indigo's, hognose, - man this is tough.
Snakes that I would some day like to keep - King Cobra. I won't be keeping venomous any time soon, but if we ever decide there is a purpose in us keeping venomous snakes at the zoo, and I find someone very qualified that can make me their apprentice... I would one day love to have a King Cobra in a floor to ceiling, and very large cage - to just admire on days when I need inspiration.
Snakes we keep that I really want to breed in the future (beside the indigo's) are the diamond python. Just yesterday I talked to Don - and I am really pumped about diamonds at the moment.