Mixing is 90% arrangement, 5% levels and 5% everything else. I've been trying to follow the roboctobus school of thought recently. Make it sound as good as possible in LSDJ alone and then maybe doing some gentle stuff on the masterbus at the end, which is what you're doing by the sounds of it.
If you're recording the tracks separately and you do a lot of stuff with grooves, sometimes they don't match up properly in the end. And also, if you're using hardware, you can end up with a pretty nasty noise floor imo.
One thing I seriously recommend is comparing your levels with musicians you really like. Think about where X artist sits their kick/bass/etc in the mix.
