What is your advice on eggs? Just try to sell them for potions?
I guess I'm looking for the generic heal, mheal, electric... so best would be to keep humanoid eggs and roll them right?

Roll anything but insect and spooky otherwise I only pick up uncommons

What do you do with the extra pets that you don't need?

Like if I target rolling the common humanoids, what should I do with the others?

throw them away

they are hard to sell

Do they simply do nothing once they are hatched if you decide not to use them?

they just stay at your petyard waiting for you to feed them or let them free ;D

So I got a raccoon Magic Heal, Heal, Electric
Is that the best and should I then continue on the woodland track?

That's a good roll imo. I prefer having mp heal first as it starts out at a lower heal rate than hp heal. It's up to you though, if you feel safer having hp heal first then you should keep looking for another pet. Woodlands don't get hp heal first on any of the pets so that roll you got on that racoon is the best you can get for that particular family.

lower heal rate?

not if you max them

but on the way to max skills your mpheal will be better than your hp heal at the beginning
lets say that a rare pet with 50 mheal and 50heal does the same amount of healing as a pet with 50heal on first skill and 50mheal on second skill