During a trip to Russia you can quickly get tired of seeing so many beautiful churches, monasteries and kremlins. When you are in St Petersburg you can even have enough of so many palaces and museums.
PavloskPalace is yet another example of the opulence of imperial Russia. And from the outside that's all you can say, but it is sublimely and richly decorated inside. If you are staying in St Petersburg for several days and have some free time then a visit to Pavlovsk is interesting.
As the town (Pavlovsk is a surburban town) is about 20 km from the centre of "StPete" it can take time to get there. If you have to prioritise which palaces to see outside town then you should go to Catherine in Pushkin (Tsarkoye Selo) and Peterhof.
Nevertheless, at the beginning of the autumn the park around Pavlovsk Palace is a gem!