Help in wanting to get the game and advice.

Hey, i want to get sims 3 because i hear people say that its better and there are more things to do in it rather than in sims 4. Sims 3 also happens to have a lot of expansions, so what expansions should be the ones i get/ are worth getting? should i get all the expansions? and should i play just the regular game for a little bit before i get expansions? Also, give your opinion on if i should be getting sims 3 or 4. one of the big selling points is i hear you can have alien children and ghost children in sims 3 :)