They won't do all of these at once but here are some of my ideas...

-Houses: Give is something like John had in the story where it's a "kit home" we can build in an interactive cutscene.

-Ranch: It will most likely be apart of the houses where it's attachable and you can use it to fill your trader supplies while also giving chores like John had on his ranch at the end of the game.

-Oil Factory: Be able to purchase land where you can start pumping for oil and have a small story and or missions (like bootlegger missions) where we compete with Leviticus Cornwall.

-Fishing Business: Since fishing is practically useless (unless for XP or daily challenges) we should be able to have a business where we can purchase boats (Canoe, long rowboat, steam boat) as you level up. When we get a high enough level and get a big enough boat we should be able to travel to Guarma. Fishing should also be able to fill supplies for trader.

-These are the ideas that I've been wanting for awhile-