Firefly,
Dunno if you're gonna read this, but I have a similar setup as yours. I actually have been gaining more Mac games alongside PC (if available, I'm almost always picking the Mac version because so far I've found them less buggy, though I still have a bunch of PC games waiting for me to get to them), so I understand that you'd like surround gaming as well as a competent external device. Well, I've said time and time again, if you have a Mac, Windows, and console platforms, the best I've found so far has been Creative's Sound Blaster Recon3D USB processor. It has USB (and native drivers) for both PC platforms, and an optical input for consoles (I have a 360). And, it actually has pretty low noise, so it works well for double amping.
I have heard rumors that a few months from now, Creative is releasing a new version of this product to fit with their Z-series lineup. That's the one I want, but the wait is really under-living at the moment, if you know what I mean.
Alternatively, if your Mac has a Thunderbolt or HDMI port, you can connect to a home-theater receiver for surround. That's kind of a bulky solution, but it works, and it has it's advantages. I personally think Yamaha's Silent Cinema is comparable to Dolby Headphone, not much between them, although receivers usually have more tweaking options than standalone DH devices.
That's good news!
Though honestly, after never owning a Sony console yet (IMO the PS1 was graphically messy, then... Halo, so I picked an Xbox over a PS2, stuck with it for online gaming into the current gen), I think I'd get a PS4 this time around. Or maybe just a PS3 and catch up on goodies I missed. I'd be tempted to buy an Xbox One and Halo 5, just to finish the story that could've (should've?) completed in Halo 3 because I'm a completionist, and return it after beating the campaign. I'm really wishing to just move over to PC now, and I'm sick of paying for multiplayer when it doesn't seem like most games take advantage of LIVE in any way better than on PC (plenty of hackers everywhere these days, too).
If you wanted to try an E12, why didn't you just ask to borrow mine? It's been neglected lately, as I'm playing with tubes and considering a DAC/amp all-in-one for my iPods.