Main thing that I noticed - too many of the songs that you're mixing start instantly with some lyrics, which means that trying to mix them is not going to be effective. I was really aware when a new song was coming in over the old one, because it was too obvious that it had been added.
For example, on the Hardstyle Top 15 2012, the mix of these two songs:
S-Dee - Music Is 10:24 - 13:09
Titan - The Hour Of The Night (Original Mix) 13:10 - 15:49
What you want to do is mix the beat from Hour Of The Night in sooner, rather than having a blank space in the song. You'd have to beat match the two and slide it under the end lyrics of Music Is at around 12:57~12:58
http://www.youtube.com/watch?feature...Tg9aV5Y#t=778s
http://www.youtube.com/watch?feature...Tg9aV5Y#t=803s
If you overlap these two points, you'll create a seamless flow as the previous song drops off, where it can mix in to the next one, without the lyrics getting in the way. The guy should say "And now, it's coming for you." as the beat is kicking in.
Even if you do a sloppy mash of the two, it'll still come across sounding more involving than just a straight song swap with 5 second fade. Aim for 15~30 second fades, by just dropping the bass out of the first song and let the second song take over at a natural sounding point. If you're mixing a song that has a big build up, then make use of it as the previous song is trailing off:
http://www.youtube.com/watch?v=yOSvyp04zNk
All of this is doable on a PC DJ setup too, just give it a try. Even if you don't set starting or cut off points for the songs, just have them trail into each other. For example, Steam Train could've started mixing into Hour Of The Night about 15 seconds before it finished, rather than just having the beat vanish.