@eekim provides tons of great feedback, most of it linked from Tank Is Alpha. Predictably a goodly chunk of it surrounds granular addressability in Tank Granular Addressability. Within is the suggestion:

However, why not simply implement structural identifiers?

Perhaps but doesn't this work against the intentionally dynamic nature of text which is in a wiki. In Augment wasn't much of the text journalling and thus fairly write once-ish? One of the things I've always wanted to ensure is that content in wikis grows and changes in reaction to the synthesis that is going on around and with it.

Part of the reason for seeking feedback on this issue is that I don't mind the in-markup identifiers, I'm just well aware that other people do. In my perfect universe everybody would be attaching [nid fad4] all over the place.

(The complexity of this discourse is a good sign of why granularity would be handy and I think something will happen in tank at some point, I just want to be sure to go to the right place.)

In Tank Is Alpha the granularity of access control is mentioned as a cool feature. I agree, I think it is likely far more useful than is immediately obvious. TiddlySpace intentionally hid a lot of that power to remove some complexity. This worked well for some folk but was very limiting for others.

Not mentioned there is Privateer which mints unique URIs for accessing single private tiddlers (read-only) without auth. It needs a UI.

Many of other comments have been addressed either in the issues or in responses on the G+ posting. The one missing thing is:

Page revision history / comparisons

This is coming soon. It's a matter of not having built it in yet. Revisions are stored and there is a tool for TiddlyWeb which can show diffs between versions. I'm slow to do this because of lack of interest on my part, but I understand that it is important to some (hi @FND) and why it is important.