Part of adding distance is getting less mechanical. (Plan smart, throw dumb)
If you are thinking 1..2..3..throw in your head, you are throwomg mechanically.
Untie both your shoes.
Tie your left shoe. (Good job!)
Now, go back to grade school and tie your right shoe thinking about all of the steps. (Grab the left lace in your left hand and the right lace in your right hand. Cross them. Loop the top lace under the bottom lace...)
How did you do? What did it feel like to be fluid? Do you want to be fluid or mechanical when you throw?
How do you move to more a more fluid throw? Practice. Practice the X-Step alone (IN YOUR HOUSE, where nobody is watching) Add the arm. Add the disc (OUTSIDE, where you won't break your wife's lamp!)
For me, I spend a lot of time figuring out my throw before I throw. Once I have my shot lined up, I get as dumb as I can (not too hard) and go. 1..2..3..pull happens whether I'm thinking about it or not.
Pred, Wraith, TeeBird, Eagle, Whippet, Cobra, Rhyno, Arrow