I have problems with the regularity of critical failures/successes...but not in critical game situations which make it really fun!!!
What I had toyed with for non critical/long term skill uses was something like an index factor to indicate general outcomes; and then added to with a roll if you so wish (which would result in the more skillful taking risks IMHO anywhoo...). So for example, if a weaponcrafter is making stuff over a year....
1 Tend to the fire boy. Output stonger muscles.
2 Try this horseshoe with supervision. Output a couple of personal metal items and few shoody for sale.
3 Producing apprentice/poor independent. Output of poor quality volume low to medium dependent on forge access.
4 Time to be finding your own forge/jobbing independant. Ouput of poor quality volume dependent on forge access. Could press for independence.
5 If an apprentice still, being taken advantage of. Average independent. Output occasional good work and steady volume.
6 Master/Good independent. Output high volume or good quality; occasional very good piece
7 In demand. Output high and good quality. Occasional very good pieces.
8 In demand; need to specialise, expand, or relax. Output very good and high volume; or excellent and average volume. Occassional excellent pieces otherwise.
9 Renowned. Lords are sniffing about. Output: Cannot keep up with demand. Very good and excellent work which buyers pay over odds for. Possibly a 'perfect' piece.
10+ Famous. Life gets political. Output excellent and high volume if well supported by apprentices. Occasional perfect pieces.
(Cash no. could be worked out as percentage of average wage)
So you would not get a novice punching above weight, or a master producing duds for a year
The extra roll could be used for a 'special' item (Phew you made that sword for the violent mercenary really well! etc)...or to risk going up/down a band (or two?).
I first thought of this whilst climbing....once you reach a certain level you can climb pretty much anything at and below that grade...and people 2 grades below just cannot, however hard they try.