@nikkon - keep in mind that you came to an internet forum with a simple question, and the responses you got were: your speakers are shit, your dac is shit, your whole system needs to be replaced, etc. I really like about half of the threads here at ASR, but the other half is just people just being mean and bashing things. Telling someone to replace their entire system is just a ridiculous response. The problem is that if you say that to an audiophile, they might half believe it, then gear lust quickly takes over and the next thing you know, they're replacing their entire system!! So maybe take some of this with a grain of salt...
My take:
1) Your speakers are fine. Go look at that graph that someone posted - they're pretty much +/- 2.5db on axis. For passives, that's fine, and way better than some other stuff out there. Yeah, maybe not ideal from a theoretical perspective, but *practically* speaking, you already know they're fine because you like how they sound.
2) For your amp, yeah, go with one of the class D offerings. You can't beat Purifi or Hypex. I've got four of the Apollon's, and they're very well built, reliable, and look nice. They've got TONs of power, are super clean, and are around $1k each, which is an insane deal given what you get. They measure better than the $10k Yamaha amp you were looking at, and in a blind test you wouldn't be able to tell either one apart (unless you did it at ear splitting volume, in which case Purifi/Hypex wins since the Yamaha will clip earlier). Alternatively, the Schiit Tyr's would probably be great too if you like those, but won't sound better than Apollon, so you'd really be paying extra just for looks.
3) For your DAC, yeah the Yggdrasil measures pretty poorly in the whole scheme of DACs. Whether or not you can hear the difference compared to AKM though is another question. Replace the amp first, then worry about your dac later if you still want to tweak things.
4) If you haven't messed with it yet, room correction might be something to explore as well. MiniDSP sells a relatively inexpensive Dirac implementation that works really well. Something like that is going to make much more of a difference in sound compared to changing your dac.