DPS balance is fickle because of how readily it can be changed mid-expansion. Now is the opportunity to get mitigation and self-sustain right on tanks. Otherwise, you're going to be living with that balance for another two years.
I would like to see a shift back towards more deliberate and active self-sustain rather than passive effects. I think that a lot of the 'Additional Effect' heal and regens that were added this expansion to actions like Equilibrium and Shake it Off need to be rolled back. If you want a job to have a 'lifesteal' theme, then the HP gains need to move towards resource-gated offensive actions rather than defensive ones. So rather than placing lifesteal on something like Bloodwhetting, it really should be on an action like Inner Chaos/Chaotic Cyclone, where it heals proportionately to the damage you've taken recently or based off of the amount of damage that you've lost. That has the added effect of coupling mitigation and burst, which is something that WAR used to do back in Heavensward (Vengeance and Inner Release also generated gauge at the time).
I'd like to see invulns revised. Hallowed was designed to be 7 minutes at a time when tankbusters occurred every 30 seconds. Modern day fights have much more infrequent tankbusters. As a result, designing interesting tankbuster mechanics and swaps ends up being meaningless, simply because you'll always choose to disrespect the tankbuster with an invuln. Either the frequency of tankbusters needs to increase significantly, or tank invulns need to move towards longer recasts. Holmgang is the worst offender here, especially after this expansion's buffs. I think it should be on a 6 minute recast, not 4.
I think the balance on Shake it Off needs to be revised, especially if Vengeance is being upgraded to provide any kind of raid benefit. If Shake is to work on all damage types in contrast to Heart of Light and Dark Missionary, then it should mitigate less and be on a longer recast.
Most of all, I just want them to look at tank balance with fresh eyes. Whoever has been responsible for balancing the role over the past few years hasn't really done a very good job. I don't know if that's due to apathy or bias, but I really want to see some change within the role.