Meteor isnt bad - I wouldnt use negate outside of medium-large scale group play if you really know how to use it. Overload and atronarch are pretty useless for PVP. WW is very strong with a good build - and bats are good too if you dare go vamp (good luck with camo hunters out there - wouldnt recommend).
atronarch is too easy to avoid and can be disabled easily. it has an instant stun and basically its like putting a long dot in the area thatll target someone. WW is the best bang for your buck ult option - but needs a good build behind it. Otherwise, dawnbreaker or meteor. Thats my suggestion.