I think the biggest annoyance by far is iTunes Connect. It's an odd beast.
It's awkwardly separate from the rest of developer centre, and have this bizarre requirement that you use a separate Apple ID for each iTC organisation, so you end up with one primary Apple ID tied to all developer programs and separate Apple IDs for each iTC account.
It's awkwardly separate from the rest of developer centre, and have this bizarre requirement that you use a separate Apple ID for each iTC organisation, so you end up with one primary Apple ID tied to all developer programs and separate Apple IDs for each iTC account.