In search of a bigger rear tire, I asked the mechanic's opinion and he said not install a bigger tire as it will hinder performance. Instead he suggested to install the rear rim of Deluxe.
Here are some photos for comparison:


The bike of the left is mine and the bike on the right (GS150) is the one with the Deluxe's rim. Both of them are wearing the same type of tire: 3.00-18.
Another thing to think about!