Well for one Google will adjust the volume issue that some people are having with their own setting to adjust the volume like volume+ does, so that's a non-issue.
As for feeling "old", I just can't agree with that. You're looking at specs and thinking it makes a difference anymore when it doesn't. The CPU is the best currently available, so it can't be "old". It's GPU can run any game available at 30+ FPS, so there's no need for anything greater, you'd just be using more battery for similar performance.
Seem's like Cereal misunderstood that you actually have the Nexus already, so you didn't buy anything at the first of the year, you bought it when it came out.
You're going to be waiting 4-6 months before anything comes close to out-spec'ing the Nexus and that doesn't even mean it will be better. It's like computers right now, we're using quad cores and barely anything even uses more than 2 cores and our GPU's are so over the top that no game except for maybe 2 that barely anyone plays can tax a top of the line system. The improvement in hardware is only needed when the software requires it, currently the software doesn't require much in terms of phone hardware.
The Nexus is the most future proof phone available, you already have it, if you like it I would not return it to wait for the next best thing. You'll be waiting months and no matter what comes out, no phone will receive the update support and dev support that the Nexus will, that's guaranteed.