RAM disk is indeed very handy and I use it a quite often but it's not something Amiga exclusive or better done. RAM disks existed long before Amiga.
For example Atari 8bit DOS's and MSX-DOS use RAM disks pretty much in the same way and they can be used just like you discribed above. I've used both systems before I got my Amiga and I still do occasionally and on both I use the RAM disk just like on my Amiga's, unarchive stuff, run programs from it, store temporary data or config files.
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On both the Atari and MSX RAM disk survives reboots and it's nowadays even possible to use battery backed up RAM on the Atari 8-bit so the contents of the RAM disk are still there even when you turn off the computer.
