I've been mulling over this idea for quite some time now.
The current riven rolling experience isn't very pleasant one. With massive kuva sources added I find myself bingerolling with the factor limiting not being the resource itself but rather my time/fatigue.
The problem is with the long animation. I need to
1) click roll
2) confirm
3) wait about 5s
4) focus myself and uderstand the new option
5) select the desired one, confirm again repeat the procedure.
With the worst thing for me being that I need to be mentally focused for step 4 and 5, and preferably as absent as possible for steps 1-3 - to avoid fatigue.
I believe I have found a neat solution that could be implemented alongside the current system. Allow for multi-rolls.
A player selects a multiplier, let's say 10. He is being charged kuva for 10 rolls straight away, but is being shown 11 mods to choose from.
Technically the player is operating at a loss here. They could have rolled the desired stats after only 2 rolls, and save 8. But the time saved, the comfort of choosing "best of n" instead of "best of 2, n times" would - at least for me - be more than enough to use this mechanic.