Direction of the top end of arena

I think it depends on the Maul squad. A Maul squad using Palp, Vader, or even zKylo will have issues because of tenacity up and TM gain. The squad I use (zMaul, zDN, SA, zSavage, SiT) had no issue with Rex because his tenacity and Chirruts cleanse don't affect anybody but Maul's daze. Sure the squad gets plenty of TM but they're hitting into my SiT with over 80K HP & Prot and he dodges a fair amount of attacks including dispels. I face enough Chirruts around 260+ speed too, just not an issue. Now if you're using Palp, you are at a disadvantage at times. Basically his opening AOE gives a ton of TM, maybe stuns a couple and then it's cleansed by one of the 3 because the TM gain is often enough to make the squad go before your DN. Just depends on the squad you're using. I stopped using Maul because after two months or so it just got boring.

Jedi can beat Maul, even before r2.

Again, depends on the Maul squads and mods too. We had a couple Jedi that manged to crack top-10 but none that could crack top-5 or ever take 1st. I think even the best Jedi were at a definite disadvantage against the better Maul squads. At my payout there's this one ass that likes to snipe even though it's not his payout and he was never able to snipe me once I put my squad in. Other's followed suit with my squad and he never sniped anybody again. A couple others might finish between 6 and 10 but that's the best I saw.