You have more than enough draw weight, but I am not sure it is the tip nessessaraly. Some do pull out easier than others, but you will loose some of those big fish whatever you do. It has been my experiance that 20lb+ fish all should have a second arrow put in them as insurance. I shoot an old round wheel at 55 lbs and have good results out to 15 yards and even with those deep shots when the fish is deeper than a couple feet.

The biggest factor I have with loosing fish is having them tangle the line up in weeds by swimming in circles - once they have something solid and close by to pull against the arrow often gets yanked out.