I think it could add marginal value, but only if it was running when the buyers came around, and they had kids, and all the kids sat down to watch it, so parents realise the potential...either that, or you throw in a spa as well, adults will like that then...
A few comments to this idea -
why a tripod? Why not a roll up screen? Tripod takes up space and will get
dirty easily.
$10 headphones for a home theatre? I am an audio buff, so I don't see the point in a home theatre with audio that cheap. Maybe around $100 each I could manage (well, actually probably not, but $100 wired would be ok). My wife however would be happy with the $10 ones