Hello there.
I saw on this forum hundreds threads with suggestions or wishes to what should be changed or added in Poser. Unfortunately none of them mentioned anything about animation controls since not many people are doing this stuff with Poser. Below you can see what I find user-unfriendly regarding animation in Poser.
If anybody has some others things to point out (but related to animation in poser) then just list them here - maybe somebody out there will read this and change something.
   

animation palette window

1. suggestions:

• add "right click menu" for individual frames (I mean when you right click on the small squares inside the window):
   .add / remove key frame
   .spline
   .linear
   .constant
   .break

• add check boxes for what should be shown (like in hierarchy window):
   .show figures
   .show props
   .show cameras
   .show lights
   .show deformers
   .show parameters
    .scale
    .tran
    .rot

• align names in left side winddow to its RIGHT side,

• make first figure in the list NOT TO UNFOLD automatically after another prop/figure is loaded,

• if there is a BREAK on at least one parameter within an actor and the actor is displayed as folded then clicking BREAK button toggles BREAKS on individual parameters (it should rather remove BREAK from already affected parameter(S) and not to change others)

1. to fix (I'm not quite sure if things below occur because of my computer or because of Poser):

• after selecting frames for more then one parameter (unfolded actor) and then collapsing that actor, selection box remains at it was thus affecting other actors,

• after applying BREAK to a parameter (unfolded actor) and then removing it and collapsing an actor, the break mark is still displayed - this occurs ONLY at first frame,

• when dragging frames to right side (left side is working fine) it is not possible to get to last frame in one move (only and always happens when horizontal slider is active) - I always have to finish at least 3 frames before last, move horizontal slider to the far right, then again drag whole selection,

• when "render tab" is in front (active), poser doesn't swich to "preview tab" after clicking on small squares inside "palette window" - but it does switch when clicking on any element in left side list.

graph window

1. suggestion:

• change design - at present all four corners are occupied with some buttons - make them at one corner,

• make poser remember how many frames are shown in graph window - do not make it 30 after each reload,

• make grid color adjustable,

• make some room before 1st frame - it's quite a task to select multiple frames including 1st one.

1. to fix (again maybe this part is because of my computer only - then ignore it):

• frame counter is not updated while changing frames in graph window (it is being updated when animation palette window is open at the same time),

• key shortcuts (for moving between frames like: arrows, tab, shift+tab and enter) are not working when graph window is active.

others

• make shortcut for spline/line/constant (better one "toogle" key then 3 seperate ones),

• make shortcut for braeak,

• let the user set rounding number for values displayed in parameters window (or at least present rounding shouldn't have any inpact on true values - they should be LEFT UNCHANGED after leaving edit mode - when using PNU I very often need 4 digits after coma),

• SYMETRY tool in menu is useless - hasn't been updated since poser 4 I think - some actors are not included (finfers starting with 0) as well as some parameters (twist on waist),

• it is not possible to make a key frame for any parameter by typing in parameter window its exact value at current frame.

All for now :)

Nice comprehensive list!! 

Although I really Doubt any new animation features will be added to poser
I would like to see a NON linear motion mixing system like DAZ studio's "aniMate" ( which I use frequently)

Also an ability  to mix IK and NON IK in the Same animation!! right now if you key some motion with IK turned  off and later down the timeline  try to
use IK it will destroy everything before that point by trying to apply IK retroactively

The ability to selectively show items in the animation pallet and a keyboard shortcut to Display  them.
A better Zoom and Pan in the graph editor
the ability to Cache or "bake" Cloth sims to PLA or MDD Files
assignable keyboard shortcuts in general BTW.

I personally have began to use C4D alot more for character animation but it would be nice to see some modern CA feature in poser.

Cheers