I'd also like to be able to offer user drag'n'drop or paste funtionality for images.
I've noticed there are two plugins that do that already - but not are not optimal:-
.https://www.dokuwiki.org/plugin:imgpaste imgpaste only works with the chrome browser
.https://www.dokuwiki.org/plugin:supa supa is fairly old, and requires Oracle Java installed
I can't comment on either of them as I don't use Chrome, and won't install Java on my web-servers (for security reasons). I only discovered them as I was interested in similar functionality.
You
might be able to modify the solution I found for my own editing purposes, to suit your particular platform:-
Beneath my home directory I have a directory called webservers, which contains directories named after each web-server installation of dokuwiki. Each of those directories is a sshfs mounted file system of the relevant dokuwiki media root directory.
e.g.
/home/scott/webservers/foobar[/m] is actually [m]sshfs://$somehtmlserver:$sshport/home/foo/public_html/wiki/data/media/
NOTE: sshfs is a secure remote file protocol used by 'nux. I "assume" Windows may have an implementation, perhaps from a third party - or you can try WebDAV.
Any images I drop or edit in
/home/scott/webservers/foobar[/m] are actually in the root directory of the Dokuwiki Media manager on the relevant HTML web-server. If the wiki at foobar.com.au has a sub-directory (namespace) called baz it'll be call [m]/home/scott/webservers/foobar/baz
I realise that may not be much help for other users of your public wiki - which is why I was also looking for the same type of plugin.
NOTE: I don't actually work on live wikis, just the copies on a local (private) webserver - then when I've checked the results, I use rsync to synchronise the changes to the live (public) wikis. I recommend you do the same as accidents can happen, and get noticed by search engines and users before you're aware of them.
Hope that helps