FIRST and most important - you didn't list your budget. Recommendations won't mean much if I give you recommendations which are out of your price range.
Second, this statement:
I'm on the lookout for a new soundcard. I've decided not to go for USB or Firewire but instead PCI.
and this one will limit your choices extremely.
1. I need it to have XLR-inputs
some recommendations:
M-audio 1010 $599 has 2 XLR inputs and a total of 8 balanced (including the 2 xlr) analog inputs and it also has SPDIF and MIDI
EMU-1820 $399 has 2 XLR inputs/mic pres and a total of 6 analog inputs.
EMU-1616M $450 2 XLR mic pre inputs and a total of 4 balanced inputs but it has superior A/D converters.
there are others available, but without budget info, that's a good start.
7. It has to work well with Asus motherboards (I'm using the Asus P5Q-E), and yes I know people here say they suck with DAWs.
I'm not sure you're going to get many recommendations based directly on your motherboard unless someone happens to have the same one and happens to have a soundcard which meets your other criteria. most of these soundcards won't have problems with specific boards, especially if you're not going with firewire, but to get a direct recommendation on your motherboard compatibility is probably pretty difficult.
9. I play the occational game from time to time. So it really should be able to use it for games as well (and again, I know you shouldn't use your Daw for that kind of stuff but no one's perfect.. )) ;-)
I do the same thing and my m-audio delta 44 does just fine for ALL sounds - as you know from my posts in the sonar forum.
10. Ease of use
based on this requirement I don't think I'd go with the EMU stuff. the EMU has a software patchmix panel that is quite complicated. it's very powerful and once you get it set up you can probably just leave it that way forever - but it's not SIMPLE to setup. there are lots of others on these forums who use the EMU cards, however, so getting help should be easy enough.