I chill my 2.5G of wort in an ice bath too. But heavy on the ice (we use the better part of a small bag,5-7lbs),& stiring wort occasionally. keep ice water circulating as well. I've chilled wort down to 67F in 20-30 minutes. But usually 70F,then use room temp spring water to top off.
It's not hard,just be a little more patient. I think,when combined with even a small starter,average gravity beers come out better.