I just recently starting micing my guitars and I feel like we have a similar issue, somehow I just don't get all that definition and warmth others do and I'm guessing it's cause of acoustics just like everyone is saying. (though to me you also look pretty far from the mics, ESPECIALLY the guitar one, staying a few inches back from the vocal mic is one thing but you're gonna want that guitar pretty close to it's mic) and I'm not saying this is the best way to fix your problem or anything, but instead of getting a better mic or trying to treat my room, I've just started using saturation plugins to add warmth. A plug-in that mimics mic placement is called "proximity", if you look up "proximity vst" you should find it, when I add that with a good saturation tool, (Saturation knob, Head-Crusher) I tend to like what I hear. However my sound is experimental and sort of... psychadelic rock, so I admittedly get some lo-fi distortion going on when I do this, I just tend to like it in my tracks, you may not dig it in yours. Proximity isn't a saturation tool though, it will just make it sound like you mic'd it closer than you really did, may be worth a shot.