The first ideas were around making a library of films similar to IMDb but with more uses. For instance, to have the opportunity to use one single platform with information about where to watch different content (Netflix, Mubi, etc). There is a great project going on in Spain called series.ly that has tried to offer a free service that is not illegal and promotes films of all kinds. Then the possibility of taking Netflix to the next level became plausible.
Many things can be improved about Netflix. The possibility of making playlists and share them. Make it more social like Spotify, but without creating a forum of discussion. The possibility of watching something with another user at the same time. Adding a history tab. Algorythms suggest content based on what the user have watched, which it's not always what he or she likes. The info of what other users are watching. Joining groups or playlists based on taste. The possibility of suggesting films to Netflix. Have the chance to pay a small fee to download the content (or give the possibility for free). Offer more languages for subtitles. Even there is a possibility to avoid infinite scrolling that brings the user playlists based on the votes (not on what has been watched). The movie/TV series of the week.
As a user of Netflix like I am, I always search new content based on friends suggestions or forums on internet where specific audiences unite to suggest content. That could happen in Netflix, and not outside of it. Nowadays, the user can only rely on stars, but that's not a fair way to judge a film, and internet users are not famous for being fair. The user should feel in control and familiar with new suggestions.
These ideas have to be should be consulted with other Netflix users. A survey was made and sent to different groups on Facebook to get different results.
The following links and platforms helped to identify some of the problems.