I learned to play “picado” (scales) more or less like “the Sabicas style”, NAMELY, playing more from my first knuckle and I was thinking about what you mentioned in the videos about Paco de Lucia’s placement of the right hand:
and I really like the idea to play mainly from the second knuckle instead, just as you said.
Do you recommend me to radically change my right hand posture or should it remain as I learned it before?
This depends on what you want to achieve regarding scale playing, and it also depends on how used you are to the former posture.
If you want to develop speed on Paco de Lucia’s technique as well as a deeper tone resulting from it then better you change your posture. There are two ways you can do that which are as follows:
1) To drastically change your posture (and possibly start from the beginning again)
2) Gradually change it by slowly becoming aware of the 10 things to avoid and trying to modify one thing at a time progressively transforming it into the way Paco play scales which -in fact- is the best in every aspect. This posture or technique also helps you to avoid injuries at short and long term, so it’s a good idea anyway.
From these two alternatives I recommend you the second one, hence with that I have seen more students succeed.
All it is about regarding a superior technique is awareness and you can get that under proper supervision, the result you want will come earlier if you start with a gradual re-development of your posture until it becomes you second nature.