Optimal size of player and fonts

Hello

I have set player size to fill the screen no matter what the size of the screen but sometimes (say on a small size netbook) it produces text etc. which is far too small for easy reading. I have not tried this on any tablets.

I guess that the alternative is to use a font/font size and player size which is a compromise and probably too small for most large modern screens (not a good idea IMHO). 

What does experience tell you is the best policy for this problem? What are recommended player and font sizes if any?

Thanks for any help.

Andrew