I want to suggest that there be a file uploader(Control or Button ) to be used to upload files from local to the required locations like Sharepoint/Cloud/Onedrive etc.
Currently there is Addimage is present based on that we can select only the images types only and not able to change the file type eventhough there is Allfiles are showing in the OpenDialog.Things to be updated like seprate control or the Addimage control to be modfied to pick any file that can be saved in the prefered location as mentioned above.
I checked another approach also using the Import control. This also not support the all files it supports the zip formate.
For Clients as developers we will not suggest to zip your file every timea and use the Import :D.
One more thing i need to add to this is while using the Export and Import controls genrated files are not usefull outside the PowerApps, if those files can access in their original formate from outside that will be very usefull.
IF we provide the Upload functionality the end user who uses the app they can easily upload thier files useing the app which is devloped in the PowerApps.
Example: Am a user i want to upload file which is present in my mobile phone or file which is persent in my local on the desktop.
If these is the requirement, to provide solution to this using powerApps now it is not possible.
If these is achived in PowerApps End user will go for the uploads provideded by the App which is built on the powerApps.