I'm looking for a mod that does not change the base gameplay (I've never played Diablo I before) but would allow me to hold down the attack button to limit the number of clicks I need to perform?

I read on another post that Diablo Clicker still worked. You can download it from here: [url=]https://freshmeat-blog.de.tl/Downloads.htm[/url] Just note that I haven't tested it myself as I'm use to playing the game without it.

I've just downloaded the Diablo Clicker from the site you linked. It has two versions. The older version uses a DLL hook, but the newer version is just an AutoHotKey script that has been turned into an EXE (the script has also been provided) so this should work fine on any Diablo 1 (and other games for that matter) as it runs outside of the game and just turns mouse clicks into repeated mouse clicks, with an option to turn the script on and off by pressing F2.

check out this mod: https: the hell 2 @ moddb.com

the auto clicker is built into the game itself. it only requires the diabdat.mpq file from the original game to run and has several qol improvements to numerous to list as well as a very active discord community.

It seems that Freshmeat doesn't host the files anymore, though the site is still up. I'm going to try to find a generic auto-clicker and report back if I get something working.

Just use DevilutionX, it has this feature built in and it doesn't change gameplay - all it does is add countless QoL options and fix bugs.
https://github.com/diasurgical/devilutionX