It's seems to be possible to poll the force value manually, it may be the case too for the other values you mention. I'll keep you informed if I need testing on that (I don't have any iOS device).
I noticed that this value is set only when event.type == "start" ; when the pointer is moving, value stays the same, even if touch area changes.
Is it also an iOS limitation ?
I guess it is but I can't say for sure !
When stylus is used (on iPad), touch is ignored.
I guess it would be possible to solve this by rewriting the touch implementation in o-s-c using the Pointer API, which is not somthing I'm willing to do at the moment, maybe someday...