Craft the greatest URF variant

Was watching a few YouTube videos and some streamers mention various thoughts on what would be a better URF. I am curious what other variations may be possible and work well together:

What sounds great to me so far would be Enemy Select URF on Howling Abyss, with lane minions on constant spawn.

There are drawbacks to being in the ARAM map, less jungle and terrain play in general, and more predictable choices all around. In fact it may not even feel that different from normal ARAM gams in the end. But it does still sound like a more hectic environment in general.

So... normal URF is a nice way to spend a weekend. But what can spice it up nicely? Just as interesting, what would be absolute disaster for a minor change in URF?