gilded ore
Classic's weight and ballistics system is much better that Call of the Wild's. Restricted to two long guns and a handgun, it feels more realistic and suitable for a hunting game. With this system ballistics could better mimic reality, making all the weapons more broadly useful and personal preference more viable. DLC would be a choice, not something you're obliged to get because it's arrival invalidates the other other weapons in it's class range.
Honestly, a broad spectrum weight rebalance wouldn't hurt anything. restricting the inventory would also make things more customizable. Taking the .270 huntsman as an example, a good middle ground weapon that will hit class 3 animals like a truck but take excellent shot placement and in some cases a long time to bring down an elk or moose. Say 7 units in weight, not as light as a .223 but not as heavy as a .338, add 0.10 to attach the tritium sights (no iron sights weigh a half pound and if they do they ain't made for hunting).
Attach the Ascent scope for 0.5 more units of weight, the Hyperion for 1.0, and the Argus for 2.0 and your main rifle weighs around 8.0 units. pair it with a shotgun like the Caversham 12ga O/U at 6.0 (minus the rail/scope) to cover all the small game you might cross paths with on Layton. Now add the Panther .44, just in case those moose try to bully you, say 2.5 units. That'd leave you with about 3.5 units of weight left, you can't carry a tent with a whole storage locker in it, but you'd have room for some calls and a medkit.
This could easily be an option applied to new characters, a choice at the character creation screen that could not be changed later in the game. It would give players the option to choose a slightly more realistic playthrough while retaining the option to have the game as it is now.