I am in the same boat. Important.
I render a lot of test renders with ArchiCAD. It's quite annoying to delete tens of test renders when you are done with them.
In C4D there is Picture Viewer, and it's great. You can render either straigth to the active viewport, or optionally to the Picture Viewer. You can select any number or all of the pictures and deleted them with just one command.
In ArchiCAD, if not wanting to build a separate picture viewer, temporary renders could reside in Navigator/Organizer as a separate hierarchy.
It should not locate in the same hierarchy as other project entities, because there are to be treated differently, as temporary files, until they are saved by the user of course. That's because we wouldn't want to save 50 test renders along our project when we save the project and leave to home. That could yield to an unnecessary huge project file.
In this hierarchy you could select any number of test renders and delete them with just one command. And maybe with a prompt to be sure, but not many prompts. You could preview test renders by doubleclicking, or by clicking their tab titles, like now you do.
It has happened to me, that I accidentally closed the whole project without saving the model. Just because I wasn't careful enough clicking the tabs and don't saves repetitively about fifty times in a row.
Of course there's also the great batch renderer in cinema 4D. And team renderer and some other additional features I would love to see in ArchiCAD some day. But I understad we couldn't get everything this time around.
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