There's no right or wrong way to mix and master your work.
But it helps if you have a good monitoring set-up. I check my mixes on my main monitors, headphones, test my mixes in mono on a grot box and on a TV. The idea is that my mixes are universal.
Mixing and mastering is different process. By your description what you need to do is engineer your work. Which involves mixing the tracks into a musically satisfying form. And that means getting the vocal 'out there'. But that doesn't mean just turning the vocal track up.
Try making room in the track for vocals. Use surgical EQ'ing. to make way for the vocals and glue the mix with some effect processing.
Or work on the vocals alone. Get them sounding right, airy. Add a touch of reverb to the vocals not to much though. They need to be tight.
When I engineer my tracks I use all kinds of plug-ins. I suggest you try iZotope Ozone 4
or T-RackS 3
. Their both great mastering plug-in that I use on some stuff. Also see if you can try Cockos Reaper
to mix in and use your plug-ins with. I've just started to use it together with the others I have and I love it.
Thanks for sending me some of your work. Keep it up. Just spend time getting the recordings done properly then the mixing and engineering become easy.