I really don't think that makes sense.
A pointing device like that isn't a drop-in replacement for touch... Some things are fine, like tapping buttons, but others are not, like anything to do with multi-touch or swipe gestures. There are also aspects of UI design that are subtler but can add frustration... E.g. drag operations with a pointing device can run out of room as you hit the end of the trackpad or mouse area but this isn't an issue with touch, so touch apps tend to rely much more heavily on drag than pointer UIs. Conversely, pointer UIs can make nice use of rollover, while touch can't. So.. You can add a pointer and pointing device to the iPad, but it won't work very well from a UI perspective.
In addition you have to fiddle around with another device -- getting your mouse/trackpad out when you need it, dealing with connection issues, keeping it charged or plugged in, etc. For this to pay off it needs to make things significantly better, at least for some general use cases, not worse.
Finally, pointing devices like you mention work best when you have you device set up like a laptop, not held in hand like a tablet.
So, might as well use a laptop, then, with software actually designed for you UI devices.
Are saying that the ipad pro wouldn't benefit from a mouse pointer? Or that wireless mouse(mice) are more of a burden to carry around than they are helpful?