Don’t let people talk you into something more complex or balanced or whatever. Machi Koro is almost certainly the game you want. A 7 and 8 year old can absolutely play it. Get the new Machi Koro Bright Lights, Big City edition. It is a refined version of the original with most of the cards from the expansions. It’s true that some sessions can go unexpectedly long, but the new edition does things to mitigate that. I got Machi Koro last Christmas for my brother’s family–who hardly play board games at all–and this Christmas they told me how much they love it. Don’t listen to the haters or hobbyists, they’ve forgotten the delights of simple, transparent, responsive, joyful gaming.