You can make macros to "manage" it for you. But jumping from 6agi -> 12agi and doubling the elemental force procs is a pretty significant damage boost. If you're playing competitively, work on figuring out the weapon swapping. If you're pugging and having fun - you do you.
For the macros, you'll want to set up two equipment sets that basically don't change anything except the weapons. Replace the set names with 2H/1Hers below. Weapon swapping takes a GCD, so you'll want to spam the harpoon/raptor strike buttons to make sure they go off. Its best to hit raptor strike to switch manually if you know you're going to need it. The Serpent Sting macro can be a number of things. I personally go with a shift modifier that updates the weapons. Otherwise it goes as normal. Basically this will make the "default" state your 2h and you have to consciously hit shift with serpent sting to switch. You can tweak it however you want to make it work.
Code:
#showtooltip Harpoon
/equipset 2H
/cast Harpoon
Code:
#showtooltip Raptor Strike
/equipset 2H
/cast Raptor Strike
Code:
#showtooltip Serpent Sting
/equipset [mod:shift] 1Hers
/cast Serpent Sting