For me its,
1) Short game, i have wasted 4-5 shots inside 100 yards before, perfect drive on a short hole = double or triple bogey, oh yea, NO PENALTIES!!!
2) More GIR's, if i am on my game, i have hit over 75% of greens, but i get one round a year like that. I am usually good for 40-50%. I need near 75-80% with my short game.
3) Putting, i am two putt machine, really need to work on making more putts
For me, its first, hit more greens, more greens = less time using my horrible short game. Make sure when i am hitting GIR's, i am getting it closer to the hole. Finally, short game, really need to stop being fearful of it, its a real negative for me.