Gunbreaker
Bring back the Draw and Junction ability to GNB: This core ability allowed for more variation, strategy, and utility that was unique to GNB that was both fun and interesting and an overall disappointment to lose.

Give GNB better utility, or more damage to compete with the other tanks: Currently GNB's damage does not make up for the utility the other tanks can bring(i.e. Vuln Up + Holmgang, Damage down + Ranged Burst + Hallowed, Healing Down at almost 100% uptime, etc.). This can be balanced by either a flat increase to GNB's damage equivalent to the utility lost, or additional utility to even out the playing field(Draw and Junction).

Don't have the Gnashing Fang combo interrupt your single target or AoE combo: It doesn't in PVE, no reason it should in PVP.

Increase the Fast Draw(Haste) max duration from 15sec to 20-25sec and implement GNB's Fast Draw buff timer onto it's job gauge: Comparing this to DRK's Darkside buff that only requires a single oGCD to maintain, with a max duration of 30sec; to GNB's Fast Draw that requires a gauge spent GCD to maintain(3 GCD's to max value at 3 stacks), but only has a max duration of 15sec, it is non-equivical in favor of DRK. Another possibility would be to make Lightning Shot an oGCD on a 20-30sec timer, keeping the same effect in order to make maintaining the buff far less of a burden.

Either make it so the shield removal from Bow Shock happens before the damage, make Bow Shock do 0 damage and decrease the cooldown, or change it to something else entirely: As it stands now, Bow Shock will do damage to the shield it is trying to remove, before the shield is actually removed, making the ability counter productive.