I've made some huge changes to the plans for the Household Rush mod, and it has expanded and renamed to Social Rush. The mod creates a challenge known as the "Rush Challenge" with several different types.
The goal of this Rush challenge is basically to entertain a group of Sims. There are two main goals, which are to keep their mood up at a certain value (which can be done by performing interactions that will give them positive moodlets) and to get to a certain level with them. Moodlets for inactive Sims will be automatically reset, so you can't get them into a good mood before the Rush challenge starts. A Sim's traits play a part in how good a mood they need to be in, and how much relationship you need to gain with them. You will be given two hours to complete the goal. Once you complete them, you will be given extra time and the new set of goals will be harder.
This is the same as Casual Rush, except it can only have one Sim, and goals will be based on romantic activities.
The one I originally created this mod for. Like Casual and Date Rush, you will be required to keep the Sims in a good mood and get to a certain relationship with them. When you complete the goals, you will receive an offer to join the household. If you accept, you will be moved into the household's lot and all the other household members will become roommates. If you reject, the challenge will end.
First Impression Rush
This Rush challenge starts when you meet a new Sim. The goal is to get to a certain relationship point within 30 sim-minutes. Depending on how successful you are, you may get an automatic relationship boost, or relationship decrease with the Sim.