Feature Request:
Ability to lock x or y coordinate in the current position of the cursor. Would allow for much easier alignments of traces and parts.
I don’t know of such a feature.
I bet there is already a wishlist bug over at the bug tracker. Just mark it as “affects me as well”. Add a comment if you feel your usecase is not explained well .
If there is no such bug report, create a new one. (Developers do not really regularly visit this forum.)
Just be aware that a feature request without a patch ready will take some time to be implemented, if it ever gets implemented at all. (Developers in open source projects typically implement what they themselfes need or find interesting.)
Some parts of what you want might be partly implemented or there is a tool that can be used to do something similar.
For part placement you can either use a very course grid or the user grid. (the later can be made such that one direction has a much coarser grid then the other, combined with the ability to place the grid origin this might help you a bit.)
The other option is the move exact tool.
For traces: In opengl interactive router, you can use the ctrl key to force kicad not to make a direction change in the trace. (I’m not really certain this exists in stable though.)
In the nightly there is also the shift key to force kicad not to snap to anything. (In stable there is a menu entry to disable snapping, but this is quite cumbersome if you only need it sometimes.)
I would suggest to play around with everything what i listed and see if you can use anything as a workaround. (At least for now.)