We should be able to build perks as mods for the weapon. A "kinetic" mod isn't a mod... it's the ammunition used. Going into vanilla D1, I had thought that we really would have been able to craft our weapons. Was let down, but accepted the random rolls on the weapons. Now, I feel that once you run the raid a few times, you're already tired of the exploring world's, and PvP becomes stale... it's hard to keep interested because there isn't much weapon variety to spice things up. Different weapon builds on the same frame can have very different feelings. Many of the D2 weapons I find worthless. Only a handful are worth using, and almost everyone is using the same ones. 98% of people use the same weapon, is not because that one is amazing, it's because the rest aren't good enough and can't be made better with different rolls.