(I'm on OSX by the way)
1) Play any bloody format -- VideoLan √ (for the most part)
2) Automatically start playing from last position video was at when player exited -- VideoLan ? (come on! Put checkbox in options, anything, just do it. I pretty much need this feature.)
3) Automatically remember last window position AND/OR size and keep it that way for all video regardless of resolution and a single keyboard key shortcut to toggle it: position, size, position & size, original AR.
4) Press "S" to toggle between subtitle files (a single key, not a key combination!)
5) Have changes to subtitles appear instantly (it's a joke that Vlan can't do this)
6) Press "F" to toggle fullscreen and window (")
7) Press right and left arrow key to seek forward and backward by 10 second (customizable, or even have two finger right/left swipes for OSX for seeking)
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9) Video mixer
10) exit app when last window is closed (OSX specific)
11) Adjust volume up/down by two finger scroll up/down on trackpad or some other keys.
That's all I want. Exactly like that. Pretty much how MplayerX is, except MplayerX is a piece of buggy garbage that can't even seek properly.
Having the arrow keys like that for seeking is the most intuitive. I don't know where the hell VLan gets off thinking that everything has to be a freakin key combination. See, OSX has this cool things called a multi-touch trackpad. How about using it?
Everything else is pretty much icing on the cake. Am I asking for much? I don't think so.