This is one of those niggles that has been around for a long time and it is time to put it right. The current image uploader is, let's be honest, well past it's best before date. File and Media uploading is also one of the most requested features. Developing our own is one solution but it's not pretty.
Having searched for various options I found TinyBrowser which appears tp be exactly the sort of tool we want. I have plugged it in to the 4.1 development code so it can be tried out. NOTE: I have done N O CONFIGURATION for this as yet so it will ignore preferred upload folders and do it's own thing (in wp-content).
My problem – as always – is that I am currently unable to test it as it requires the GD php library which I do not yet have installed. (I really must try and get around to this. I just worry that it will trash my setup and installing php modules can so easily trash a setup!)
One possible advantage of using TinyBrowser – and I make NO promises here – is that it may be possible to also get it working with the other editors as, while it functions as a tinyMCE plugin it can also be used in standalone mode. But that remains to be seen.
First task is to try it out to see if we can use it.