I did roughly the same as most everyone on here - witch mama (surrounded by family, which offered nice point boosts for all those kids related wishes), vampire dad with Golden Tongue, Golden Fingers - I didn't want to give my parents the labor time in the hospital so charisma was a must - it didn't always seem to help, but towards the end it did. Had one career LTW on the go at all times till the easy skill ones were done, and then the game got SERIOUSLY tedious towards the end because no one wanted to budge.
The elixirs were an absolute lifesaver, the parents never slept a night in their lives - potent invigorating elixirs from the start, till kid 1 (vampire) had a really easy LTW (Master of the Arts, maybe??) and was able to get a moodlet manager. Once I had a couple of kids or higher on the lot, I didn't do birthdays in the house - always kicked across the lot with a parent + cake if they were too young , or an age of instant potion if they were child or higher. Most of my witch kids were converted into vamps for higher skilling if they didn't have an LTW for a different occult - I never converted my vampire kids.
Collecting was easy, since mama kept doing conversion ritual in her spare time. I did Master Alchemist early and spent the almost 3 days before I kicked her out (right before mom was due to give birth) creating ~200 Essence of Magic. I also set up as many LTW in advance as possible, like the others said - my fairy bloomed the perfect garden, everyone who was waiting to go to work/had time before the next birth fished for the perfect aquarium - I stocked a pond in my house with the 10 fish from the store so there was zero travel time, and the remaining 3 were done in salt water with easy-to-buy bait. I used a transfiguration table (?) for the first time to create a 50k bottle of nectar so I didn't need quite as many trips to the consignment store, and the mom learned MA from the book to spar with the kid to finish Physical Perfection (I never did find a dummy or board breaker in the store).
I had a ton of potions stockpiled, because my opening strategy was to get dad to work on his guitar portion of his LTW while mom bought out the elixir shop - and I lucked into 4 midas touch in the first few days. So I merely befriended the maid and threw parties with his "household" - ie ALL the NPCs in-game when I needed RIs. A couple of potions and a love charm later, they were the right age, and the teens never had to leave the house. In fact, my kids never went to school. The babies & toddlers all got heavy sleeper + something related to the LTW they were slated for - I did things in groups so that I could switch them around if the right wishes rolled up or they weren't a vampire when it would've been helpful (One Sim Band!). When they aged from toddler to child, I assigned workaholic. The teens got a PT job with the right schedule depending on when they aged up, and once I got established, the merely skilling sims were being turned out of the house at roughly 4 days from birth
I'm pretty pleased with how I did, although I'm wishing that I'd interspersed more career LTW at the beginning, since that really slowed me at the end. However, I never want to see a crying baby again for a while! (Maybe a few in the memories challenge...)