I decided to try free version of UMotion, out of interest. The tool feels pretty promising. I tried it for maybe 30 minutes and here are some findings.
Please discard things I mentioned that are actually already implemented, I didn't bother to check the manual yet. Tested on the latest version, which I downloaded just before.
I also got a couple of crashes, when selecting sliders in that floating tool box, it crashes UMotion with some Unhandled Exceptions, related to IMGUI I think.
Edit: Sorry for the wall of text.
Saving - Editing animation does not have a save feature, edited animation is changed automatically? This means that trying some tweaks and then discarding a change becomes cumbersome, if any clip must be duplicated before opening it.
Wish: Opening project doesn't remember scene character that was used last time. Maybe add option to try to use last used scene object, it isn't found then discard it and make user pick a new character.
Centering - now it seems Unity standard F to focus gets disabled when UMotion is activated. This is frustrating, I usually use this to jump to different parts of skeleton / scene.
Camera follow - I couldn't find an option to track position of picked object. Sometimes it would be useful to be able to make view follow root / hips. Even better if with option to disable some axis (to prevent vertical movement of character affecting camera follow).
Selection/keying sets - can't find anything like this. It would be great to be able to select Animated Properties, then click some button to create new group. These groups would be selectable from a dropdown, and autokey/key would automatically set keys on these bones. Also, it could have secondary option to also show those bones only i.e. upper body group selection would hide other bones, allowing to concentrate working on certain bones.
On screen tool box
Rotation Tool window - Locking joint free angles is essential. But seems like this is only for all objects, not per object?
Bug? Pressing M to key, changes tool box to show Muscle Groups window? I didn't retry replicating this, maybe it was caused by activating sync selection, but I happened every time
Bug? Maximize view (shift space) and the restoring the view closes the currently open animation... this is not so fun, as sometimes I don't have that much screen space, and maximize view is useful to get overview of keyframe layout.
Keyframes - Move to previous or next key with keyboard shortcuts.
Wish: Reset time line zoom. There is zoom in and out, but usually it is convenient to have reset zoom, so one can judge the overall keyframe distances.
Play animation - When play is stopped, animation current frame marker should return back to start frame where play was pressed. I know there is start and end markers but this would be more convenient when tweaking certain part of animation. It would be easy to tweak some keys then verify animation is working, then continue where I was working.
Green scrub bar - is it / would it be possible to move current frame marker by just pressing some key + mouse dragging over dopesheet? Similar to middle mouse dopesheet drag? No I must concentrate to try to hit that tiny line in top bar for something I need all the time.
Selection/Synchronize with Clip editor - Seems to select 3d skeleton matching tracks in Animated Properties. But rotating bone and releasing mouse also deselects selected bone on screen, and from Animated Properties. This does not make any sense. To me, logical solution would be to keep animated properties selected, and screen selected bones should stay selected too, and only picked/active bone should have brighter color than others that are selected in Animated Properties.
Wish: Move up and down in animated properties with keys. Not sure if it is possible now.
Skeleton / bones
Wish: bone box display mode. Would make it easier to animate without mesh, with boxes it is easy to judge facing direction of head, torso and legs. Would be great for fingers too.
Wish: sticks bone mode seems to be only unlit. Could it be using shaded shapes too?
Wish: bone diamonds don't actually scale the "standard way". When making bones thinner, the height of root "pyramid" should also get shorter. Also, it would be nice to have some sort of minimum scale, now acceptable "thin" bones for limbs makes fingers to be way too thin to be usable.
Customer support service by UserEcho