I've been thinking about replaying this, but a question before I do. Is there really any point in most of the weaponry you pick up? Seems like upgrading Dan's rifle makes most other things you pick up effectively obsolete.
Depends a lot on the situation imo. In most regular encounters there really isn't much point in picking up a weapon that you wouldn't really need, but since you can see what weapon it is before picking it up, you can make a decision based on that. If you kill an enemy with a shotgun for example, and you feel that it would be helpful to swap for that as your secondary so you can run the rest of the enemies, it can help a lot in a narrow area. Or if you see a sniper rifle and you're in a good position, that can help too.