I understand you will NEVER, EVER add online multiplayer. But here's one thing:
For the Local Multiplayer, whenever you select that mode/option, you'll be asked to enter a name and same for anyone who plays it. So like that, you can invite people in your game, only if they are near you (in house/building, irl).
It can be difficult to implement, or not, but I'll understand if you do not want to or you can't. Feel free to choose, and good job for this patch, I liked it!