Sadly none of the recent improvements apply to gtkplastic.

With release .742 a part of this uservoice is implemented, namely the possibility to jump from a selected branch in the Branches view into the Branch Explorer (fixing that other uservoice) :
https://www.plasticscm.com/download/releasenotes/5.4.16.742

What remains for this uservoice to be completed is to add support for multi-selected branches and the relevant commands under the "Branch Explorer" sub-menu.

BTW, I want this on Windows and "robl" wants it on gtkplastic. ;)

Finally, as a tip to "robl", similar to the filters for the table view one can add inclusion/exclusion filters in the Branch Explorer as well. These filters can be toggled on/off. (At least on Windows.)

Slightly related to this:
https://plasticscm.uservoice.com/forums/15467-general/suggestions/5125136-show-this-changeset-in-branch-explorer

Actually, this was duplicated by me here: http://plasticscm.uservoice.com/forums/15467-general/suggestions/9588258-branches-view-add-submenu-branch-explorer-for-q

I'll append my comments here, for reference:

Currently, there is no easy way to jump into the Branch Explorer from selected branch(es) in the Branches view.

This would be very convenient since it can sometimes be cumbersome to locate a specific task branch etc in the main Branch Explorer, while it's quick to find it in the excellent "Tree view" of the Branches view.

I'd like to have in the Branches view a (partial?) clone of the "Branch Explorer" submenu from the Branch Explorer view:
* Show selected branches in a new diagram
* Show selected and related branches in a new diagram
* etc

Also, when only one branch is selected I'd like a command to simply switch to the standard branch explorer and focus the "head" changeset.

Excellent idea, we want this ASAP! ;)