I know this is not really the answer for a GUI however, I couldn't help but notice how the specific characteristics mentioned are already available with
youtube-dl if you add a few extra options to your command.
First, to control the quality of a
youtube-dl download you can use the helpful
-F option to list all the available formats even showing which format is "best".
youtube-dl -F http://www.youtube.com/watch?v=P9pzm5b6FFY
Here is the output:
[youtube] Setting language
[youtube] P9pzm5b6FFY: Downloading webpage
[youtube] P9pzm5b6FFY: Downloading video info webpage
[youtube] P9pzm5b6FFY: Extracting video information
[info] Available formats for P9pzm5b6FFY:
format code extension resolution note
140 m4a audio only DASH audio , audio@128k (worst)
160 mp4 144p DASH video , video only
133 mp4 240p DASH video , video only
134 mp4 360p DASH video , video only
135 mp4 480p DASH video , video only
136 mp4 720p DASH video , video only
17 3gp 176x144
36 3gp 320x240
5 flv 400x240
43 webm 640x360
18 mp4 640x360
22 mp4 1280x720 (best)
The best quality here is option 22 so . . . change the
-f 22 like this:
youtube-dl -f 22 http://www.youtube.com/watch?v=P9pzm5b6FFY
If you do this in an open terminal it shows progress in % until completion. Finally, if you want to download multiple videos at once . . .
Just use CTRL+SHIFT+T to open a new tab in the existing terminal. Use CTRL+PGDN or CTRL+PGUP to navigate open tabs.
It can't hurt to know.