Congrats on winning Lena!!
Some other things that are useful; Writing comics builds street art and painting as well as writing so that a great way to knock those three out. They're also very quick so make writing challenges easily achievable. Consignment store and inventing were bugged for me so I couldn't achieve challenges on either, this wasted time as well. Was really annoyed too when I realised I'd misallocated martial arts so she couldn't train up anyone to spar with as her sister had logic. Tutoring people makes friends so I'd combined with charisma although she got enough friends in other ways. Favourite combo was using social networking to invite over a childish snob with a good sense of humour. One silly face and gossip later and you've learned three traits, told one joke, made an acquaintance and used the sim finder app; four skill challenges contributed to.
I didn't buy anything for the lot at first beyond two sleeping bags and a wall with the boy band posters on. This gave enough environment to give a decoration moodlet to counter the hates outdoors moodlet. I also scheduled them to sleep during the day so they wouldn't be scared in the dark and they'd be skilling in library/ elsewhere with lighting during the night. Soon as they had enough cash they got the sleep slave bed and other household items. Fulfilling little wishes took care of moodlets otherwise. It was a really nice change to promise things worth 150 or so rather than waiting for 5000 point wishes to roll for Lifestates Dynasty. Anyway, this kept them fulfilled and generally focused. I didn't have any trouble with tantrums after the first day or so.
Was the architecture career also off limits as you could makeover someone's house to include a bounty of skilling objects that you could then go and use?