Ask HN: Which features would you want it an online video editor?

With the growth of online video streaming platforms like youtube, we found an urgent need for people to edit their videos to make it into something that grabs people's attention. As attention is what get them views and likes and more views equals more ad based revenue.

Most requested features in an online video editing webapp that we received were- 1) Ability to upload from and upload to youtube directly from the video editing service 2) Remove and Replace video background 3) Adding royalty free video shots in between the video clips 4) Adding free background music 5) ?

Apart from these - What would you guys want in an online video editing platform?