If you haven't reached a plateau, I wouldn't change anything. Ride a routine as long as it works. You don't have to change just because you hit an arbitrary number. If the numbers are still rising, you're still improving.
If you have reached a plateau, there are endless options. Beyond Bodybuilding outlines the basics of how to construct your own routine. If you have BB - and everyone should - you should study the first chapter, which describes a lot of powerlifting cycles and the logic behind them. You can use the principles to construct work-outs which fit your training schedule, recovery time, boredom factor, etc. As an example, PTTP uses 50 reps per move per week. You can play around with the sets/reps/days schemes by riffing on ~50 reps/week. 50 reps is 2 * 5 * 5. 48 reps is 2 * 2 * 2 * 2 * 3. The variety is endless.
Alternatively, you can keep doing PTTP, but switch your presses and deadlifts. The Bent Press - Did you mean Side Press? - can be replaced with any other sort of press. The deadlift has a ton of variants, too. You can also use different equipment: kettlebells, dumbbells, short bars, fat bars, Fat Gripz, even the weight plates themselves. These aren't exactly the same movements, but the strength you build carries over to your main movements. You may also find you like these movements more.
Ultimately, you will have to build your own routine to get your best results. Someone else's routine is a set of training wheels. Eventually you have to take them off to ride.
I am actually doing the side press now but would like to move to the bent press for a while to answer that question.
This is very helpful though. Guess I'm just a bit paranoid about getting optimal results.