After working with VMix replay over the past few years, I have come across a few things that I would like to see added or improved upon in the coming releases.

Camera Audio Changes
Following audio from the selected camera is an incredibly important aspect of replay. I would like to see the ability to embed other audio sources directly into the camera input that would be tracked during playback of different cameras. For instance, I have additional Dante nat microphones coming into VMix separately, I would like to attach those to certain cameras angles for playout.

Importing Clips
Clips should be able to be imported into the replay buffer for the ability to more easily playout things like highlight reels.

Music Setting
I would like to see the music setting attached to events/event lists. This way during playout of a highlight package, the music could automatically be enabled/disabled with the playout of certain events. Ideally, this would come with the addition of being able to select multiple music files. This way you could select from multiple different audio files for different music selection for various highlight reels. This could be a similar dropdown to the current playback speed column for each event.

UI Overhaul
The UI should be adjusted so that you can view two or more event lists side by side. This way you can have a general event lists with all clips, and then in a view directly next to it a package you are putting together.

Assignment of Colors to Events
I would like to be able to assign colors to events just for the sake of organization. This would allow for clear visual division between clips from different quarters of a game for instance.

Expansion of API
There are many things relating to VMix Replay that are not externally available on the API. Effectively, I would like to see almost all of the data in the replay.xml file somehow available and with more shortcuts to make elements of them editable.

Web Controller
Although this would be a long shot, everything in the replay UI should be in a web controller. This way you can operate replay fully remotely in web browser. This would allow for remote operators of replay. This is a feature that I would be willing to pay significantly more for on a per license basis.

Weird as i can see all replay angles move (more then one) simulatiously using a jog-wheel. Have you checked the replay options ?