You've got a fun style evolving. I don't know anything about LMMS so I can't offer up any advice specific to the DAW but I might suggest a few mixing tips that might help :)
Sounds like you could experiment with layering drum samples. You can start to build your own rich drum sounds by layering snares that have different frequencies & fattening up that sound spectrum. Example; you can get a nice fat mid snare from the amen break, layer it with a thin 909 snare. Then try adding an extra or so. You can get really creative with layering and even apply it with basses and pads :D
I'm not sure how much panning you're experimenting with but feel free to throw a pad to the left or right. Hi hats can get panned hard in one direction or the other. You can make room for everything and clean things up at the same time! Panning will create the illusion that sounds are louder than they actually are which will let you turn down levels here and there to help create space for other instruments. Experiment ;)
I remember when sidechaining was a huge deal. If you're doing hard dance genres you might want to see if LMMS has an option to control the volume of an instrument with the signal from another. Example; you can lower the levels on a bass synth for a split second every time a bass drum hits. That will clean up things and give the drum more punch by momentarily making room for it. For dubstep, I always sidechain the synths, basses, & pads with the bass drum and snare. It really adds punch to your drums.
Hope this doesn't seem like I'm being mean. I always leave reviews like this when I like a persons musk. Some of the kids I've reviewed over the years went on to do amazing things, music or otherwise. I think you'll be something special if your not already. Keep writing keep living ^o^