I've finished the story mode and collected all the treasures, journal entries, journal notes and optional conversations.
With that I unlocked everything I could see in the Extras
> Bonus
submenu:
- Add-Ons
- Skins (Nathan Drake: 12 skins, Samuel Drake: 11 skins, Victor Sullivan: 5 skins, Elena Fisher: 7 skins, Nadine Ross: 4 skins, Rafe Adler 5 skins)
- Weapons (21 weapons)
- Render Modes (19 render modes)
- Game Play Modifiers (10 game play modifiers)
- Character Gallery (59 portraits)
- Concept Art Gallery (23 galleries)
With all this bought, I still have 31 "Unlock Points". Is this normal? I couldn't find any use for those remaining Unlock Points. If there are other unlockables I didn't mention here, where are they?