What kind of transparency would you like to see from them? For some things, like active secret investigations how would you expect them to act transparently and publicly?

They could disclose their warrants after cases have closed and there are no loose ends.

That'll never happen. Even if the case is closed and there are no loose ends for that particular case, it would still reveal the collection methods used, potentially impacting other foreign intel and FISA related cases.

Maybe. They could probably redact the 'how' details. And even if not I wonder how many of their methods are truly secret.

EDIT: typo

I expect all actions by the courts to be entirely public and freely available. If it can't be public, they can't act.