As someone who deals with entertainment lawyers all the time, I have to say it's NOT a good idea to put work like this out in the public for a number of reasons. Lawyers and lawsuits are expensive, so most media companies won't touch anything where the ownership/authorship is even slightly questionable. It's simply not worth the risk. At best they'd go, "well, that kind of show might work, let's call [known successful producer in the genre] in to see if he has interest coming up with a show in that vein with our I.P." A writer in such a position has no recourse because a genre or type of show isn't something protected under Copyright, especially if it's something as vague as "a sitcom version of Lost In Space".