Some time ago I came across the video platform "Vimeo" in the internet.
Since I had - and still have - almost no influence on the quality of my media that I want to publish on YouTube, I decided to open an account at Vimeo.The quality is very good.
The link to my new channel:
I have already rendered some of my presentations in HD (720p) quality and published them on this channel.
Since the video files now have large sizes, anything between one hundred and several hundreds of megabytes, I recommend to start the download of the stream and wait until at least two thirds of the stream have been downloaded before starting to watch the video. Of course, it all depends on the speed of your internet access and your computer.
On the Vimeo site, there is another channel on Samos with several contributions named "Samos Island" by a user called "PolykratisP" which I recommend too.