Well, here is my oppinion on ARURF:
I think its bad and its not fun to play. I dont mind the general idea behind it, random urf propably has huge potential, but then on a different map.
I think ARURF on HA might work and could be fun to play. The problem with the current one is that you get a random champ, but are still forced to farm and lane with this champ which sometimes might be impossible. On Ha you dont care about this since you only fight. In addition, my biggest fear is that riot is planing to replace the normal URF with this mode. This would realy \*\*\*\*\*.
Why not have an ARURF on HA and a normal URF on SR from time to time, this might be the best solution imo.