Though a poor tinkerer, I've been brave enough to try something more radical
1. Changed the trigger spring for a softer one
2. Slightly hand polished the trigger part which engages in the hammer
3.As the hex screw on the trigger blade couldn't be moved, I put a very tiny piece of inox nail in its hole, set with some very light glue (the white one kind, for paper), just to prevent it could fall during reassembly.
Now I have a close-to-competition level trigger, extra sensitive with a short course, and the influence on the rifle accuracy is just amazing. I just systematically put the safety on and insert the pellet just before shooting, what I admit I didn't do before.
I know I should have taken pics, I know....