How to evaluate consistency?

I particularly like Tjpld's '"smoothness" of my balance curve' definition. My curve shows that over the short time I've been trading, I had been flat for too long during the last half of the period. Consequently, I had to change my trading plan. This was all as a result of lifestyle changes.

The balance curve is a great "personal indicator".

Any measure that contains the standard deviation of profits (Sharpe Ratio or T-Score) is automatically incorporating a notion of 'smoothness'.