In no particular order or estimated delivery time:
end-to-end 10-bit video processing on the CPU (subset of filters)
color management on the CPU
duck audio
make it easy to add 0.5 or 1 second transition on timeline
audio noise reduction
open HEIC images (already works on macOS, work-in-progress in FFmpeg)
hardware accelerated decoding for GPU Effects
read Kyno XML for name, comments, tags
SMPTE 2084 PQ HDR
HDR preview (in-app, not external)
additional editing modes/operations (slip, slide)
fullscreen playback on current/single screen with on-screen controls
project media management (automatically copy or move to project folder, automatically convert)
set metadata (artist, title, etc.) in export
archive project
raw video processing - e.g. CinemaDNG
multi-camera editing features
convert generator UIs to QML
add keyframes for generators
add partik0l generator
circle VUI control for Vignette and Crop: Circle
generic filter UI (MLT service name and table of parameters)
OpenFX and VST2 plugins using generic filter UI
multi-track transition
generic transition (MLT service name and table of parameters)
add CMX EDL import
add Kdenlive XML export
add OpenTimelineIO import/export
add presets to Filters search
add option to view timeline waveform per channel
add transitions to Playlist
add speed param to Export > Codec
add option to reduce number of encode threads for Convert, Reverse, and Proxy jobs
improve the appearance of video-with-alpha clips by showing with checkered background in source player
background removal
universal search
add a base VUI that adds indicators for in and out points and a toolbar to invoke filters:
Text, Size/Position/Rotate, Crop, Color, Chroma Key, White Balance
improved UI for nested projects (MLT XML clips)
multi-select support for Properties
multi-select support for Filters
option to include intermediate thumbnails in timeline
ability to set the poster frame for a clip
add Recent and Most Used tabs to Filters chooser
more columns and sorting in Playlist
clip markers or flags
turn off all effects switch
aspect ratio lock for VUI rectangle control - e.g. when used with Crop: Rectangle
motion blur for motion-animated things like Text and Size/Position/Rotate