A lot of articles on the subject and a lot of opinions. I think that the major flaws are:
1- The deal has a sunset clause that allows Iran to develop nuclear weapons in the near future.
2-Trust but verify. The UN cannot inspect Iran nuclear sites without issuing a 23 day notice in advance.
3-Iranian military bases are not subject to investigation, …period.
4-The deal does not address Iran’s ongoing ballistic missile program.
5-The deal does not have any provisions to stop Iran’s support of terrorism.