Believe it or not the guitar is a two handed instrument…pick hand & fingering hand,from many yrs of playing & teaching i noticed that alot of the guitars tone not only comes from the fingers BUT also the way the pick strikes the strings..

One top tip is to turn the plectrum onto it side slightly instead of just playing with the tip (works for me ) notice how the tone of the guitar changes depending on how you strike the strings,imagine your hand is a kinda tone control for the guitars sound,the hand should float around the gtr guided by your <EARS>

I find This is especially noticeable with acoustic guitars depending on the body size