Have you been able to try the k712?
How is the k712 compared to the 990 in "fun" and competitive? I've heard the k712 adds a but more bass compared to the other akgs but is it still bass light?
I've also read that the k712 has accurate imaging but central imaging is a bit blurry.
The 990s worry me due to how bright everybody makes them out to be.
I own Beyer DT990 and couple years ago bought AKG K712+second hand K702 for that neutral reference.
(+"retired" tape keeping parts from falling HD595 Sennheiser)
K712's bass is pretty equal to DT990, though not fully.
Anyway you don't want more bass than that general amount, because any lower frequency sounds would fast start burying simultaneous details seriously.
Or you would have to make own equalizer profile for more competitive gaming.
That's where K702 has clear advantage with accurate neutral bass keeping details always more easily distinguishable.
Obviously at the expense of at best average "fun factor" with bass neutral HRTFs of Creative. (Dolby Headphone's bloated bass still just barely tolerable)
In details K712 wins about same amount. Though in some sounds DT990 did better in side by side comparison.
Likely because of K712's frequency response having dip around 3kHz while in comparison DT990 is flat in there.
(Headphone.com used to have superb tool for comparing frequency responses)
Headphone profiles of Creative's Super X-Fi (available for DT770-990 models but not K712) would no doubt make that completely moot point in positioning accuracy.
And without clear and easy time difference cues front and rear direction positions anyway depend lot more on accuracy of HRTF.
Hence customizable HRTF would be advantage in that no matter the headphones.
Simply because headphones can never create something not existing in the signal driving them.
Because of better comfort I've lately used mostly DT990.
Beyer's velour pads are simply softer and because of manual head band adjustment they don't rely also on pressure to stay in place.
Unlike AKG's "automatically adjusting" head band.
For music you would likely want to drop 8kHz band 4-5dBs in equalizer for DT990.
But neither are AKGs any treble covering headphones.