I think that Unranked Arenas could be very popular with lower skill players.
I'm sitting here on my 1-6 Marauder with my ~800 rating friend and we've been waiting for the solo q to pop for over an hour starting at 7:00pm on a Friday. The PVP community is shrinking because new and low skill players, as well as non-pvpers are reluctant to q up for ranked matches. Those who do play ranked are the same few players over and over again, who ironically complain nonstop about win traders and yet still quote leaderboard rankings. The Group Challenge Skirmishes are fun; especially for 2v2 and 3v3, but its hard to convince players to play without getting some sort of reward. Sometimes I can get an unranked Arena, but I'm sure the q prioritizes Warzones. I think more players would be interested in ranked if they could consistently practice arenas. Also, an arena q where I could q up with an undersized group and fill up to a 4v4 would be great. Unranked matches would have almost no incentives for players to trade wins, and with a higher population, it would be almost impossible.
The whole point of this is to entice more players to try out PVP, arenas are extremely fun and you have more agency over the outcome than in a typical 8v8 warzone. Please consider adding an Unranked Arena Queue.