Sorry for the late reply, everyone. I've been super busy with work...
So, I created 3 sims: a Good vampire, an Evil Klepto spellcaster and a Goofball alien (the alien could have been human as well, it made no difference, but I wanted a full non-human crew
) They all also had the Loves the Outdoors trait, and the vampire and alien also had Insider (the spellcaster just had no room for this trait).
I decided to print out all possible aspirations with their milestones, so I could easily rearrange them as much as I need. I don't have the Bust the Dust kit, as well as Journey to Batuu, so I didn't have access to these aspirations, sadly. All the others were printed out and arranged by me. I started with removing the ones that take too long, since we couldn't switch between aspirations, as well as the ones that can be failed due to randomization (like winning some event). Then I divided the other aspirations into three piles, one for each sim, and tried to arrange them in future order of completion (of course, I moved some later both within one sim and between sims, but I still had some idea of what was going to happen). The starting ones were: Soulmate for the vampire, Computer Whiz for the spellcaster and Bestselling Author for the alien.
I tried to group aspirations by similar goals (regarding skill levels, relationships, etc.) and also considered the goals that can be done while working on a different aspiration, but will be counted once you switch to another one. For example, my alien was playing musical instruments while waiting for her book royalties reach 25,000, and this time counted when she started Musical Genius ("play instrument for 75 hours".
The vampire mostly had easy aspirations that don't take long, especially skill-related ones (Child of the Moon helped him complete these really quickly). The spellcaster couldn't accumulate aspiration points quickly because Computer Whiz takes a lot of time. Instead, he was working as a freelance programmer and mostly created web pages that give a lot of fame points. When he reached level 4 fame, he could choose a fame perk similar to Connections, which helped him finish the aspiration quicker when he needed level 5 of the Tech Guru career. The alien was working on Comedy books only, and publishing them also kept giving her Fame, so she could buy the perk which gives you more money for your creations. On the first day she finally got over 4,000 in royalties, she stopped writing, and had to do it again only after three weeks.
In general, the vampire mostly worked on skill-related and family-related goals (he adopted children for the latter), the spellcaster worked on mischief-related and sorcery-related ones, and the alien worked on creative ones. I didn't do any aspirations that require taking a vacation. Also, sometimes I kept forgetting about donating to charity or stealing something within a day, so my multiplier is not as full as it could be.