1440p is super nice simply for the fact that 1080p screenshots on messageboards don't blow up your entire screen anymore.
As far as gaming, the best way to go is to run in native resolution and tweak the "Render Scale" slider down as needed.
I bought an underpowered GTX 1070 not knowing that 6 months later I would want both 144hz AND 1440p. Whoops. No regrets though. The screen real-estate is a great help for work and art and Heroes of the Storm objective timers lol.