Since you didn't specify, I'm assuming you're using 2.2.0-b2.
"- recording/storing timing only when i start recording. currently it still records upon joining the world with all the chunk loading and preparing the shot stuff."
Disable auto-recording in the ReplayMod settings.
"- better seeking. it sux. it fails/"crashes" alot. _-_ "
sucking as in "being slow": press Q, jumping will be near instant in exchange for replay quality
failing as in "freezing the game": fixed, will be in -b3, see https://www.replaymod.com/forum/thread/2548#post10649
"crashes" (or other issues): https://www.chiark.greenend.org.uk/~sgtatham/bugs.html
"- added hotkeys to create and remove camera keyframes."
Read the docs and/or click the arrow in the bottom left and/or check MC's key settings.
"- i'd like a keybind overload to use a button (hammer like spacebar) as a trigger/switch to a kinda "camera placement mode" until the mouse key is released. it currently occasionally even sticks in the tool ui without any chance to get the camera rotated."
No idea what you mean.
"- corelated: the tool ui being the default workspace. "
Also no idea what you mean. What's the "tool ui" and what's a "workspace"?
"- setup time keyframes with a timescale parameter. it's more intuitive then dragging time frames relatively."
Z, also: read the docs.
If you're suggesting completely removing time keyframes and replacing it with something else: No, far too much work for practically too little gain.
"- disable the autoplay when entering the tool"
Again, not entirely sure what you mean.
If you mean that the mod should automatically pause when entering a replay: No, that's technically not feasible. There isn't any single point where we could pause that wouldn't be either after an completely arbitrary amount of seconds have passed (which would be more annoying to unpause every time than pausing manually would be) or before MC has fully loaded the world and properly positioned all entities. I.e. either entities wouldn't be where you'd expect them to be or chunks wouldn't yet be loaded or it would load everything and just arbitrarily pause after a second of playing when you don't really expect it.