While it is possible to do some very creative trees, keep in mind that splitting a single calling between ranged and melee will result in a weaker (reduced dps) of either spectrum. You're better off building one calling into a pure ranged dps and one into a pure melee to increase dps.
However if you're looking to be a jack-of-all-trades but master of none that's cool too.
i'd add saboteur as your 3rd-i'd lean towards the sab for the 5% dex teir 1, plus the snare bomb can come in handy. of course if you're hell bent on survivability than go bard, the bonus to your health is right at the first tier.