Apart from the Youtube search, are you planning to add gestures (back 10 sec/1 min, forward 10 sec/1 min), or advanced player options in the pulley menu (browse subtitles even if name.srt != name.avi, subtitles downloader (like in MPC or UMPlayer), audio delay, etc.)?
I have trouble reading some files though, but it might be related to gstreamer. The default Sailfish player has the same problems with these files (which work properly on my computer, .mp4 and .avi). Some mplayer support someday would be great.