Like Kean mentioned, if you are having trouble deciding and do not see any positives in getting it, you likely shouldn't.
The biggest reason to me worth getting the game again on PC is down to the graphics and the fact that I did only play the story once. I cane easily play it again and get so much more out of it because I know I missed a lot of details and easter eggs. I am not the type to 100% a game either so I can do all the smaller missions and such I didn't do on console on PC which will lengthen the game for me as well. There is also the fact that most of my friends are PC gamers and will be getting a copy so I will have plenty of people to form a gang with.
Mods are something as well but I am not counting on that as a reason cause it may be blocked entirely.