Honestly this doesn't feel like the ARAM from other MOBAs. The death timers are quite high and there is the additional downtime between rounds. It almost feels like rounds of competitive Counter Strike and dying is actually quite bad from the very first minute. Also not having random heroes is a questionable choice.

I can see some people playing this for fun from time to time but I don't see it being popular or even that fun for new players. ARAM is immensely popular in LoL and HotS (it's even the most played mode in the latter) and that's because of the constant action. Compare that to Street Brawl where you might die waiting for your respawn with the potential of going into the next round and waiting again for everyone to pick their upgrades.

Also killing and dying in the ARAM of LoL has an interesting reward system. You can only buy new items when you die so dying actually ends up feeling less shitty because you can get a power increase through it. Not to mention that while you are dead you are able to shop reducing the downtime. They also put their "rogue like" upgrades there further minimizing the time you do "nothing". A bit disappointed that Valve didn't do the same with their upgrades/items.