Would be great if the various pieces of the Upload were more modular so devs didn't have to dig through and copy a bunch of source code into their project just to add a couple of buttons to the control (like validation messages, file text, icons, progressbar, etc). Feels like the control is kind of half-baked.

I think the most common scenario is that developers just want to tweak the template slightly. It seems like kendoUploadFileInfoTemplate attempted to provide this, but doesn't feel like a complete solution.

That is why I want to request a similar template which preserves all the Upload features but allowing slight modifications, or separate components that represent the uploaded file pieces. Currently, I had to dig into the source code to figure out how to reproduce the status messages and size display.  If there were components for these elements that would not be necessary. 

There appears to be a allowedExtensions (Whitelist) but not a disallowedExtensions(Blacklist) link to docs

  public uploadRestrictions: FileRestrictions = {
    allowedExtensions: ['.jpg', '.png'],
  };

Provide an async mechanism to confirm action before removing files (eg. using Observables).

Same functionality as jQuery upload at https://demos.telerik.com/kendo-ui/upload/directoryupload