I have almost always left Tyros and now Genos settings where they are.. I record individual tracks into Logic from Genos (every track, every drum has it's own track).. Once in a while I will put some gentle EQ in addition.. To me, Yamaha has always been experts in their 'mixing of sounds together'. Individual sounds are great. and while some would argue, the piano on a Korg, or Roland might sound better.. I find, The Yamaha will be cut thru the mix and be present. Yamaha products work well, when you sum up several tracks.
My earliest mistakes in being a recording engineer, was EQ'ing everything too much.. Of course in those days, electric instruments, the choice of mics we had to use, the speakers themselves, could be an issue. Today a lot of that has been eliminated..
Mixing is indeed an art.. Like with music, there is always something new to learn.. A good mix is also dependent on a great arrangement. If you have several instruments all playing in the same two octaves, it's gonna get muddy.. Sometimes, thinning parts out, or lower/raising volume as sections go by, that can help. Other times you must mix the music as it is.. In your DAW, I would look at each track individually with the eq analyzer section, to see where the majority of it's sound is.. At this point, you must decide. which instrument is the most important, and for how long. some volume changes, panning some instruments off to side, hi/lo pass filtering..
Usual convention is to record things flat, and then adjust eq later.. It is often more effective to notch EQ in some instruments. If a lot of instruments are busy in the 1 K range, notch one or two of the 'not the most important instrument in the song'.. Notch, and perhaps move another band up, (make it fairly tight) and boost it gently.. You want to think of instruments in a song as colors, if you've got a painting with 7 different 'reds' it most likely won't be as effective (or look good) without other colors..
You do not have to hear every instrument clearly all the time. In some songs, yes you do.. but other times, Some instruments do not have to shine all the time.. I think of a song as a stage with a lot of items on it.. The spotlight, moves around, gets stronger on some item.. In a good mix, if the arrangement is perfect you can let everything shine, providing they are playing in proper registers, and leaving space (silence is an instrument too)..
With a mix, you want to direct or guide the listener's attention..
If you have two guitars, fulfilling the same function, you might want to pan them wide, or let one be more in the spotlight and the other a bit in the back ground.. My observation has been, depending on the type of music. the brain can follow 4 - 6 different 'threads' of musical data.. more is an instrument is really supporting another instrument. Once you get too many different things happening, it turns into a mess, and the brain, dismisses it, or loses interest in trying to make it cohesive.
Obviously get to know your room, speakers etc. Although it's great to have expensive 'flat' monitors (and sometimes they are not flat). If you know they are bass heavy, don't put as much bass as you would like.. You have to listen on headphones, play on other systems, to get a grasp of this..
Also plug in a favorite CD of music you like/ or is similar in make-up to your current project.. You know the CD is going to sound good on a lot of systems, so notice what it is doing..
Sometimes, just leaving recording and playing tracks flat, and then putting a final mastering EQ is the easiest, and clearest thing to do.
I on occasion use Steven Slates FX-G Mastering module or Ozone 8.. Other times, after trying them I decide. the piece sounds better with no final EQ mastering on it..
You might even try different mixes, number them, and write notes or save the song project.. Then you can A/B the mixes, on different speakers, headphones, etc. and get a sense of what works. None of this is written in stone, because every song is different.. Even the key of song, can greatly effect piece, causing some instruments to play up or down an octave to fit the arrangement.
If you haven't already, look on you-tube for instructional videos. There are a lot of great videos there, some of them are crap too..
Good luck.