My problem with his accuracy has little to do with dropped balls, although less drops would of course increase his completion percentage. Also, from memory, Jason suffered from just as many last year as Donovan this year imo.
My problem with his accuracy is this: I am constantly surprised at this lack of passing skills. He fails to regularly deliver the ball to receivers in stride, failing to put them in the best position to suceed after the catch. Especially in the short to medium throws. High, low, too hard, behind them, etc.
A true #1 would be nice but wouldn't change that problem. Maybe finding receivers from Cirque de Solei, instead of the NCAA, would.