After playing for 3 years on and off and still being a Live Gameplay myself for a MOBA before being inducted into the Army, I just want to give some insights on the current Battle Arena as well as will try to point out all salient issues that needs to be addressed or assessed, which ever comes may be.
Battle Arena is a pretty good alternative when you are tired of grinding against mobs and, in my opinion, gives better Legend and Eternal rewards (if opened in highest floor reached Legend Maps)but issues here and there do exist.
To note: There are 3 builds viable in the Arena;
Glasscannon(Low Endurance, High Damage Output, Mid Crowd Control)
Tanks(High Endurance, Mid to Low Damage Depending of build, Low Crowd Control)
Controllers(Mid Endurance, Mid Damage, High Crowd Control)
Our First Issue is Tankiness:
Being tanky is OK especially for 2v2 for builds that needs to be tanky enough to deal with 2 opponents at once but when made deliberately so that they can outlast others in the arena while also dishing out damage is a frustrating experience. The Set responsible for such a stat spike is Faun's Gifts that scales HP and Resistances through Luck on gear. With a Crystal Affix Luck that caps at 225% plus the Epiphany set and throw in some flat HP epic affix, this is one of the highest HP value spikes I've ever seen. To make things worse, Crushing Blow is currently anchored/ effective only to PvE which gives those with Glasscannons and Controller builds no choice but to deal consistent damage and/or proc more forms of CC(Crowd Control). This is the most effective build path because simply, they do not have inherent weakness.
Next stop, Damage Mitigation
Forms of Damage Mitigation is welcome but if the character mitigates damage more than what is fair/necessary is too frustrating. Ever seen a Tank with 300k HP mitigates 800k to 1M Damage? That is 2-3x more than the character's HP. The biggest one that mitigates damage is Block affix, to note, it has higher cap than Dodge(45 vs 30). And yes, it only can be affixed on an OH Weapon using Obsidian but still, Crystal Legends with Block chance can drop making Tanks Block chance insanely higher. Currently, dealing with Tanks is extremely limited making them the niche build as the saying goes: "If you cannot beat them, join them. May as well mention "Di Immortales" build.
How can this be addressed?
Tankiness in this game is a gamebreaking issue because it forces players to go the same making other builds unwelcome to the mix. I believe that each build should have its own inherent weakness so that a build is not strong against every other build. The direct approach, in my opinion, is to nerf Faun's Gift's effectiveness. It's spike is mainly anchored to the Crystal Affix Luck% which heavily multiplies all flat HP percentages. However, there are other affixes that gives bonus HP but the most balanced would be is the Vampiric Touch which, in lieu of additional HP and % healing through max health by bleeding, it removes HP regen.
Additionally, the Damage Mitigation through Block chance should be nerfed. Currently, there is a limitation on which piece of gear can a Crystal Affix Block(OH Weapon) can be placed but unfortunately, Crystal Legends of any piece of gear can drop and possess the Block chance crystal affix. The quick solution to this is to nerf Block chance to 40% or down until 30% to go along with Dodge affix. Block, unfortunately, synergizes with Shieldwall + Reflect Damage + Cerebral Vortex, can kill anyone without even getting in range to deal damage.
Indirect Approach is to introduce a new Set made specifically against Tanks in the arena. Crushing Blow is severely ineffective against other players. Let's call the set "Giant Slayer". Dealing damage against players or monsters which has higher HP than you causes them to take additional % damage based on their max health over 2 seconds up to a cap of 10% of their max health.
Favorable values would be, deal 0.5% per rank of enemies' max health per 15000 health difference in over 2 seconds.
Now, why 0.5% per rank if it has a cap of 10%? This cap can be raised by Epiphany as of any stat. It also forces a build to be extremely squishy to be able to gain the full advantage of the set.
Furthermore, the 2 seconds allows the set to not be extremely overpowered and would allow Tanks to mitigate damage by regeneration.
To test this, you are a Glasscannon build with 1 HP vs 100k Tank build. Without raising the stat cap, you deal 10% of the Tank's max HP, 10k over 2 seconds which you deal 5k per second. Consistent Damage dealers will refresh this set effect.
Second Issue, Crowd Control
Crowd Control(CC) offers a bit of protection for those with Glasscannon and Controller for build as well as providing meaningful and interesting interaction for some skills. Most forms of CC are achieved through casting OH skills or Legend Affix procs. The problem with CC is: the Character can be able to stack several forms of CC in less than a second. To add to that mix, CCs in the form of Elemental Critical(Freeze for Ice, Stun for Shock and Immolate for Fire which, as I always observe, has Knockback on proc). While it provides strategy and a bit of protection, being able to proc several times within a short period of time is very cumbersome to deal with. To note, the Rogue with Vault(Causes Blind) + Taunt. The skill Dispel doesn't help as much unless you have decent Cleanse or Purge stat.
How can this be addressed?
In many ways, Crowd Control is important as a mean of a possible way to make hits land or a form of protection against those with dealing consistent damage. As observed, different forms of CC are more effective than one form of CC. Placing a bit of "respite" in between different kinds of CCs makes for a breathing room to apply your own CC to your enemy. This can be achieved by placing a bit longer special cooldowns to all CCs in the Battle Arena and reducing all their duration, which should go the same to Trophies. Alternatively, as stated, Dispel is ineffective as it will only remove the current persistent CC/s and will not prevent any incoming more within a few seconds. Adding an effect that we can call "Respite" allows a player to be Immune to all CCs within 1 second allows for them to properly penetrate a CC storm that Caster/Hitter Campers are notorious for.
Overall, in the long run, the Battle Arena should have its own special stat scaling without having to introduce new elements. As a former Live Gameplay myself to a MOBA with more than one type of Game Mode, this will be very cumbersome indeed as several game modes needs different considerations but it will better reward players who dares to go out of the status quo and show that being different is not as punishing as it should be.
The most balanced build in my opinion?
Glasscannons. With clear strength and weakness.
So that's it and welcome to my first thread ever created. Bored, do not have plans with this long rest and can't go anywhere so may as well create one with my thoughts on it. Feel free to criticize or agree to disagree.