This is a pretty quick hackjob to see what it would be like to add mouswheel support. There are is a nontrivial mismatch between the current Pointer model and how mousewheel actions work. Before continuing I'd like to have a good think what impact forcing it in would have and if there is a better approach.
That said, the code for this on jdotrjs/hack-in-mousewheel if you want to fiddle with it.
♡, jdotr