Hmmm...in no particular order...
1) Echis....the thought of bleeding from my gums and orifices just isn't appealing
2) Bitis...seen pics of a puff adder bite, and it is most unpleasant
3) Dendroaspis...the idea of suffocating while trying desperately to breathe is something I could do without...
4) Naja...Necrosis AND neurotoxic symptoms?!? No thanks!
5) Bothrops...the thought of my tissues being turned to jelly isn't something I'm looking forward to.
6) Agkistrodon piscivorous...having a nasty secondary infection and losing an appendage isn't fun I'm sure
7) Crotalus adamanteus/atrox...See Bothrops...yikes!
8) Tapian....perhaps this should have been at the top of the list, but again...no particular order here....
9) King cobra...I'm sure it's not pleasant...the upside is I don't have very long to worry about it! 
10) Daboia russelii...beautiful serpent, but I imagine my opinion might change once I was "kissed"...
-AzAtrox