NRowe, NO BIG PROJECTS. ;) Now, that that is out of the way. Are you planning on purchasing High School Years? If so, focus on which Sim(s) you wish to take through high school. Don't let yourself get sidetracked, we're down to seventeen (17) days to release. I say this in all earnestness. Write down the idea, and pursue it at a later time.
If you're not going to get HSY, then go for the project you have in mind. Do what makes you happy.
And I have a hard time playing with fewer that four Sims. That couple without kids is hard for me. I must fill the house! I also have autonomy slammed on full. This way I can focus on the Sim (such as Erik) and their goals, while knowing the rest will be all right. I also employ the Pause Button. Remember it's your friend. That way if one of the other Sims is going from yellow on their way to red, I can intervene and set things right, again. I love MCCC.
I have always been one to take the harder path, though. I think it's in my DNA. If I don't feel challenged, I get bored. And, I'm almost never bored. Truly. I have come to recognize, if I can't manage my household of Sims, then it's possible I should stand down from playing that day. Because it's me. I'm tired or worn out, or something. But again, that's just me.