Suggestions for Content

[HummingBeard]

WEAPONS AND UPGRADES:
a weapon that can be Fully Automatic and Semi-Auto would be good to have in situations late game where there are a LOT of Mutants and Canibals. i suggest the MP5 or MP7, giving it a 20 round magazine that can be upgraded to a 30 round one, have low damage per shot but good accuracy and a medium rate of fire. make it hard to get by making it a treasure hunt of sorts. you, as the player have to locate and hunt down the Operatives that are also hunting you, all who have firearms and that set up bases in Key Locations, which would make it possible to get a VERY good use out of the island on the lower right of the map, the bigger one that is there. turning it into an Enemy Compound where you need specific items to clear it and then get the loot inside, including the SMG and it's upgrades as well as Upgrades for the Rifle and Revolver as well, which would make it worth the effort.
EDITED WEAPONS ADDITION 1:
Red Dot Sights for the Pistol, Shotgun and SMG if it is added, making them stackable up to 3 so that all the weapons can get them without having to save-scum to get enough.

BUILDABLES AND BLUEPRINTS:
need to add more preset buildings to blueprints like Log Walls, better Defense Towers with Spikes on them and other defensive buildings. a good addition would be specific "upgraded" variants of already existing buildings that add more defense to them, allowing them to be more useful lategame.
having specific defensive blueprints and blueprint upgrades being possible to be found in the Compound i mentioned that SHOULD be added on the lower right large island would make for a good way to make it a challenge to get and making it so it takes actual effort to get ahold of. specific Keycards would be needed to access specific buildings, leading to the player having to Hunt Down specific targets that can be found listed on one some of the corpses scattered around the island as is.
having a special weapon as well like a Grenade Launcher with craftable custom type grenades, whos blueprints must be found as well would be a good addition, but making it ONLY become obtainable AFTER killing the last boss before you choose to either stay or leave the island, meaning you HAVE to stay to actually get it.

OTHER ARTIFACTS AND SIMILAR:
more artifacts that do specific things, some being buildable while others being single-use ones that kill enemies within a certain radius, but can also kill the likes of Kelvin and Virginia, but only if they are downed to begin with, allowing SOME space for errors.

ALTERNATE HIDDEN ENDINGS WITH DIFFERENT OUTCOMES:
like a Nuke! having a Nuke in the Compound would make for a cool hidden "ending" of sorts, and having different quest items like the Plated Gold Armor and the Artifact would create different versions of that ending etc. would expand upon the game more without it actually being "canon" if you will, but still making it a worthwhile thing to pursue. COULD make the Nuke, or whatever is chosen to deal the "killing blow" could only be unlocked as a possible way to end the game AFTER having finished it Normally with both the "Stay on the Island" ending AND The "Leave the Island" ending.

these are my ideas so far. might add some more later on if i come up with some. but these ideas would add a LOT to the game with Replayability in mind.
might come up with some Co-op only scenarios as well that forces at least SOME form of Co-operative gameplay, making it more of a Team Effort to get some of the late-game items that could be added into the game at this point.

feel free to add your own ideas, as long as it stays consistant with what could be added and found etc on the Island as is regarding the story and enemies etc.