Although the CIA would appreciate that and it's part of their smear campaign against Wikileaks, I don't think a leak website should wait with publishing dirt on country X until it has collected dirt on all other countries in the world. That would make no sense.
They were doing the opposite, releasing some documents and holding onto others for their own strategic reasons. It was always super shady, compounded by the fact that much of it was driven by one man’s ego.
Whether they held on to documents for strategic reasons, as you claim without presenting any evidence, doesn't concern me at all and it shouldn't concern you. What matters is whether the published documents were genuine leaks, and for all that we know they were. That's why Wikileaks was prosecuted and is being destroyed.
Imagine you leak some important classified information to Wikileaks and they don't publish it. You'll just send it somewhere else. There are hundreds of journals and thousands of journalists to whom you can alternatively send the information. It's frankly speaking stupid to claim that not publishing a leak "for strategic reasons" could somehow be harmful. It is also worth mentioning that journalists do that very often for a vast number of reasons such as national security, their own security, protecting contacts, protecting sources, fear of legal repercussions, political agenda of the editor in chief, etc. There is nothing special about Wikileaks in that regards.
What was special about Wikileaks was their policy of publishing everything with only minor redaction and, most importantly, without asking the befriended intelligence community for the green light first. That's what normal news outlets tend to do, unless they have a very high level story like Watergate.
Come on, we all know about the dead mans switch. Or does that not count for some reason? With regard to your last paragraph - they had no published standards about how they treat the data they are entrusted with, and no governing body to ensure transparency, and that led to the shit show they became. I didn't and don't trust WL org any more than I do any government you can point me to.