Is it possible to upgrade every single weapon in Rift Apart? I dont want to blow all of my raritanium on weapons too early in the game if there is not going to be enough of it later on in the game to upgrade the good weapons?
There is more than enough Raritanium to upgrade every single weapon in the game fully. There are several ways that you can actually farm Raritanium in Rift Apart so you should check this out. It will let you always have a steady supply of it to make sure you are not having to skip upgrading weapons.
The Raritanium that you find from the crates is finite but you will also get it from killing bosses and these can be farmed and repeated to get infinite Raritanium. Grinding is boring but it will allow you to fully upgrade all weapons before you get to the end of the game.