I want to provide my 2 cents about my arena experience in this patch! Some of this might have been mentioned before or is already on the list to be patched, but I still want to highlight everything that seems important to me personally.
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Rhamphyre's attack speed is too slow. It looks like he is hitting in slow motion. I think the balancing is well done, and if OP rogues like Gyro get nerfed, I think he fits in well. But watching this mighty creature hit so slowly makes feels bad. Lets make him look as badass as he deserves to be.
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It would be nice to have these stats available:
Total mastery points in my possession
Total mastery points on the enemy board -
Having better statistics in the graphs, for example, being able to see how a damage bar came together: how much damage did the omega/attacks/augments/synergies do.
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Option to open up the damage graph and synergy graph at the same time, being able to hover over synergies and highlight their impact in the stat meters.
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Better highlighting of units on the board when hovering over your synergies to be able to identify the board faster.
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The naming and highlighting of the "disconnect/reconnect" and "play again/restart from checkpoint" buttons should be clearer and they should be easier to identify in a split second (blunt example: in green and red) to prevent missclicks that make you pull out your hair... 😅
in example: "play again" can be interpreted as playing again from checkpoint and "restart" can be seen as restarting the run. -
Ebb line / Gyro line / Bulwark bonus / Fighter bonus / Behemoths / Wind - feel overpowered in that order.
Behemoth imbalance comes mostly from the feature (bug[?]), that basic synergies give the full bonus to composite synergies.
(Fighters plus Behemoths are a freewin)
it could be good to keep the full basic buffs until the composite synergy is activated, as high stage illuvials feel underwhelming compared to the lower stages, specially when the composite syngergies are not activated yet.
in example: sear has full fighter bonuses until 2 behemoths are placed at which point he will lose the basic synergy full bonus and gain the composite bonus.
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Scoriox / Titanor line / Empaths / Berserkers - feel underwhelming in that order.
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Having multiple copies of the same type of ranger weapons feels weird, for example, if you get 3x staff.
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It could be nice to be able to put a checkmark down which makes your waves start instantly, so you don't have to press start and can speedrun waves. Obviously, this is not important until after launch, where there is more time to experiment with niche QOL improvements.
I just wrote down what came to mind, as I feel like this is a good way to convert my experience into feedback 
I understand that most of this is QOL and the priority right now is to push the product, and not polish the game yet.
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