Didn't try the settings with a lot of games yet, i mean 1440p and GTX 970, so far played MechWarrior Online which using CryEngine 3, and what i heard its heavily dependent on CPU, which i dont have a good one to pair with (i5 3550). FPS around 30 to 70+, heavy gunfight will be around 30+ i guess. Really really heavy gunfight, with missiles, lasers, autocannon etc, 20+ fps...

Tested DOOM, which to my surprise, performance is good with ultra setting, guess its a optimized game.

Played the division as well, framerate around 25 -40+ fps, not a pleasant experience, sweat. lower down graphic didnt help much, but still there is improvement. Wouldnt recommend you to upgrade to 1440p with GTX970.

I just discovered DSR function where can virtually set res up to 4k in my 1080p monitor. But it came with smoothness problem. So if i tune down res to 1080p in 1440p or 4k monitor, does it have similar problem?

Overall, erm, not very satisfied, i guess this is the pc master race mind, haha. I used to set high-ultra graphic settings, so far not very smooth, depends on game, when there is not much going on, its ok, which is like 40 fps and above, once it get intense, then it is noticeable that 970 cant catch up, not like very bad, but once it get noticeable, then you will frustrate dy. Played below game so far:

1. MechWarrior Online (play this mainly, once it get intense, will feel the lag, but not that bad, still enjoyable, ultra settings, not much improvement with high, so i go with ultra)
2. The Division - hovering around 25++ to 50fps, okok to me. regret to buy it, game not nice. haha
3. Mortal Kombat - set to ultra, fps not that nice, but playable.
4. Havent tested Project Cars yet, cuz too intense. Stressed playing that.
5. DOOM - The BEST game so far, played it without trouble with ultra settings on 1440p, so touched... @@

Suggest you to wait next year as planned, might as well i upgrade my pc also with new CPU and GPU together with you.
Nice one, liked to have that 980Ti to complement with 1440p. Not sure if you also tempted with those g-sync monitors, so tempting to get those ultra wide monitor like x34 predator after using this U2715H.

Both of you guys specs totally owned me.  Hope to have CPU like both of you.