21:9 for gaming now, or 16:9 1440p now, and 21:9 later?

So im torn. I have a 27" 1080p 60hz 2ms monitor that is 7-8 years old. Looking to upgrade since I just upgraded my machine. i5 6600k, 1070, 16gb ram. Right now I'm playing HOTS, Overwatch, Dota 2, Rocket League, Doom. I know Dota 2 and overwatch don't support it, guessing HOTS doesnt either. I'm not sure about the rest.

My option is pull the trigger on a ultrawide now or get a 27" 1440p, 144hz, refurb acer xg27 for $299, than get a UW in 2-3 years when prices drop and hopefully by than they support it.

The reason I want a UW is the immersion when gaming. I don't do much productivity on my PC. Just gaming, social media, reddit, email, etc.