José,
my recent registrations sound more professional because I went back to school. There is a lot around to learn, if you have the time and the patience and a good midifile can be an excellent learning tool. Before recording songs like Sweet Home Chicago and Route 66 I spent hours listening to midifiles recorded by professional musicians, trying to play exactly the same notes. This goes for the solo's, the chords and the overall arrangements. Even listening to the Cavatina midifile, I was amazed to hear how the strings were beautifully orchestrated.
With a program like Power Tracks you can display the notes played on a small keyboard in the higher part of the screen. If you slow the tempo down, you can see even the slightest nuances played and actually learn a lot.
When I was a teenager I used to do the same listening to my guitar heroes (Hank Marvin, Eric Clapton, Carlos Santana and later guys like Charlie Christian, Django Reinhardt and Joe Pass). At that time all I had was a gramophone and my ear; since the records were 33 rmp there was no way to slow them down to better understand a solo. Besides, slowing down the record had also an effect on the overall pitch.
Today, with midifiles and sequencers, it's all so much easier.
So, if my recent registrations sound more professional, it's not my credit: I am simply copying what much better musicians do.
For those who can understand german, there is an excellent site; for 15 euros they sell you a midifile and also the relative style. First you study the midifile and then you have at your disposal the right style to play your song. I can really advice these styles to anyone; besides, they have styles for all the current arrangers (Roland, Ketron, Yamaha -even a few for the Tyros).
The address is:
http://www.styles-music.de/