I don't really care if our character is rich. I care if they are able to go out and do interesting things (which most shapecrafters seem handicapped in doing for lots of reasons), if they retain agency so we the players aren't trapped in bad situations without recourse (which shapecrafter madness severely compromises), and if they are happy and capable of having things like friends (and most shapecrafters are very much not).
Basically, becoming a shapecrafter seems to make it harder to have adventures or people you care about and damages agency fairly severely. It sounds like the opposite of actually fun or enjoyable in any way.
Considering we are going with Sigurdr, its fairy easy to get wanderlust and friendly for the character if we will want to make a shapecrafter afterwards, same goes for stoic calm, so those aren't really things to bring up.
And even if we don't, for some godforsaken reason, pass down friendly and stoic calm, there is nothing saying, so far, that we need to actually start apprenticing for shapecrafting BEFORE making good friends. It will need a lot of orsthirr, after all, if it costs anything like the seidr spells. At most, we would need to keep a herd in our soul if we choose to not have another life like Halla's, spending most of the year home aside from going on adventures most summer.
As for agency... again, Horra did showed us how there can be an outlet to focus on the obsession. We can even do another explorer, by going around the world and pick up interesting traits from whatever animals/monsters we encounter.
Also, i heavily doubt IF would take away our agency without us choosing said drawback, like with every time we upgraded our Fylgja.
Closest to that was rolling for negative traits for the kids, but even those, we could influence to a degree.
As for trapped with no recourse... i have no reason to fear IF pulling the rug like that, because we would build said inheritor from the moment Charred Soul gets passed down.
While i would like if the shapecrafter training would be organic, i agree it would be better to start on it on our terms, so, preferably an inheritor that was curious or interested about the craft even before the inheritance but one not yet apprenticed to any shapecrafter.
As for most shapeshifter not being happy or having friends... again, friendly trait and why wouldn't they make friends before learning shapecrafting?
And i doubt any of them are unhappy or they wouldn't have chosen to become one. the closest to unhappy was Horra, but he has focused his insanity/obsession into revenge, of all the things. Of course that would make everyone around him miserable.