Equal respect reflected to you, too. But please read again that post, it only has one paragraph devoted to the costume. The rest of my argument lies on (1) higher attack stat, (2) dealing initial damage, (3) why dealing initial damage is better than no initial damage, and (4) better synergy with BT, Wilbur and Falcon. My basis is on my experience with the Man-Lion when I got him way back in 2018. He was my first fire legendary but I just can’t remember whether he was my first maxed 5 star red or did I allow him to be overtaken by my Ares when I got the latter in one of the Atlantis summoning as a featured hero. Ares was maxed to serve as tank and for over a year, he did his job well. I have 4 other maxed fire legendaries in Mitsuko, Grazul, Gravemaker and Jean Francois. Out of these 6, JF sees the least action in raids and in wars. I am not regretting maxing him since he may still have future uses and he prevents my Master Lepus from going insanely weak if I ever take the bunny to defend.
And I agree, the OP may need to find faster heroes but I think that that when he gets used to slow heroes, he will find hidden gems in other slow heroes, too. Just like what I experienced. I have used Azlar in 2018 and I am still using him now against GTV defenses and other green tanks.
I am currently working on Marjana to 3/70 and I still debate whether to ascend or not since there are other better hitters in the coming future like Gefjon or Reuben. I have 2nd GM and 2nd Mitsuko standing by and sitting on 18 mystic rings but I plan to get them at least to 3/70 and only ascend them if I got any of those 2 future fire legendaries.
This game is not a sprint. It’s a marathon. That means, you ideally will be playing this game for a long time. And since you’ll be with this game for quite some time, you may love having an ascended Azlar battling it out in maps, events, raids and wars. In truth, there are better heroes than him but you will have to either spend much getting them or wait patiently until your luck smiles on you. But if you only plan on hanging on here in just a few months, yeah, go ahead, max JF. If you get used with slow heroes, you will love SOME of them as they tend to be powerful. Getting used to fast heroes will make you avoid leveling slow ones and that will hamper your entire gaming experience.