Same feedback as most of the other guys: You really hit a big wall once you can start building, especially because the game feels almost fast and not like a idle game until that moment. I believe there should be some more unlocks before portal to keep the speedy feeling up OR some clearer instruction on how far you have to get to advance.
Also: I really don't know what some upgrades are supposed to do, e.g. the first clone relict upgrade. Do you need to have the money to upgrade a body part but the money is not being spend?