I have had some experience in Immortal Dynasties and have a few tips of my own:
(1) My recommendation for the founder's super-max is Sculpting or Painting. If you have your founder supermax those skills, then you never have to force your spouses to bang out 25 ice sculptures and get ice personality except for the founder's spouse since he can't sculpt himself. Cooking, Fishing and Gardening are fine but they aren't really going to be an issue until your founder has aged into an adult - remember, elders have at least 10 days of life left so it's not like the instant they grow old, they'll drop dead, so you won't need Ambrosia until your founder is close to growing elder.
(2) Skills I avoid - Guitar et al(for obvious reasons, though it could be useful for a founder since he starts as a young adult with no skills); Charisma(Super-Friendly is a godsend to keeping your best friends and it's impossible not to master Charisma because just TALKING to people raises the skill); Photography(unless you lock your baby up until he's a child and get a camera by then, it'll be next to impossible to complete the Paparazzi challenge because your heir won't have anyone he doesn't know to snap a shot of)
(3) Moving in a bunch of townies is a good call, especially if they have useful traits. In my current run of this challenge I moved in the Working Friends; Tori switched to Culinary and topped her career quickly thanks to her traits and got me a MinusZero fridge which will store death fish and life fruit which Monika gathers since she's a natural Angler and Loves the Outdoors. Madison helped bring in money and Ayesha is the one who was my founder's spouse and baby mommy but she also was the painter and sculptor, getting Ice Personality before my founder did! Even though the house has six members, I am not concerned because I've got things planned out - there is still room for the first heir to marry and have a baby and since there are six members in the family now, there won't be any twins or triplets which could spell disaster for an Immortal Dynasty even this early on.
Claire Ursine is about a level six or seven in fishing.I am so surprised nobody has moved her and baby Ursine in before now. You don't have to use Claire as a spouse but she could fish and baby Ursine could paint and sculpt and be a potential gen two spouse.
That's something I didn't think about before I started my most recent ID attempt, but regardless of how this goes, I might try that next time.
More tips:
(1) I don't know if this will cause Metro to ban Imaginary Friends but I use Imaginary Friends as the spouses of each heir. It saves a lot of trouble having to spouse hunt and run into glitchy NPCs that become too old to breed, sort of what happened to Sound Man with his first wife.
I had Madison VonWatson make some Metamorphium potions for the future and I love the made-real Imaginary Friends!
(2) Supernatural tip - while everyone says to befriend teens and vampires, they forget the fairies! I read that fae live five times longer than normal Sims, so if you have your founder best friend a fairy who is a young adult, chances are he'll stay a young adult by the time your founder is an elder.
(3) Be careful if you choose one of the Showtime professions to be your immortals-to-be's career requirement, especially Singer. I am going to LOATHE Vocal Legend after my founder gets it, because he CONSTANTLY gets demands for sing-a-grams that I HAVE to do in order to get the required experience. This pulls him away from his sculpting and slows him down in his other requirements.