I don't think Primedice will change their jackpot model. The prize will remain attractive, but it is hard to attain. The number of bets has reached almost 110 billion at Primedice, but no one has claimed anything from the jackpot prize yet. Perhaps, many bettors has got the number with required bet amount but they didn't check their bets. I believe, we would have seen some jackpot winners if the jackpot system was automated.
The best thing is to play normally without minding the jackpot because if you only play for the jackpot, you will likely lose most of the times but remember to play manually and always look on the numbers that shows on your screen so that you won't miss it if ever you hit the jackpot numbers.
They shouldn't change it because it will be unfair for those who spend millions already trying to hit that jackpot and besides it wasn't easy to hit it anyway. They should not worry because they can earn more than that jackpot amount. It was somehow a nice lure or promotion that primedice got. No wonder why primedice has no promotion because their jackpot prize is too huge already.