i am dealing with muddy mixes right now and it is bothering me.  like the whole bottom end feels like it has a heaviness.  i don't feel air in-between the instruments.  even in your earlier stuff where you espouse mix trouble i still hear the distinctness and space. one part of me knows it is an arrangement problem.  and part of me also feels like it is a problem of using electric bass and hardware instruments. and then part of it feels like my actual mixing itself or lackthereof.  part may be vocals, cheap mic, or recording too much room noise.  urgh.  it probably isnt even that horrible for how bad the problem feels.  how would you start to troubleshoot?  arrangement first?
listen to it. (i realize you have already done that, but i don't know the next step because i haven't listened to it)