I started doing this too, but use Antimicro (https://github.com/AntiMicro/antimicro) instead of Qjoypad, since I find it to be more configurable. I don't use it as a replacement for a mouse but a keyboard instead. I configure it for specific apps where I need repetetive keystrokes, such as :

- VLC when I need an easier way to seek media by various amounts, speed-up/slow-down the video, play next in the playlist. Using the controller frees me from being hunched on the keyboard

- Any document reader to navigate pages

It can of course be configured as a replacement for a mouse, but the precision in my experience was way lower.