I think if the mod needs any criticism, it's that there's a very stark lack of clarity in terms of how the bosses work.
I definitely agree about this. Once I have enough time, my next goal is to try to make their mechanics more clear in-game.
Terraria's bosses already function similarly to a bullet hell, but they don't have a DPS cap, and the most complex interactions they have with the player are increasing stats for leaving their biome, or occasionally being invincible with an obvious animation to indicate this invincibility. Think about the Moon Lord's eyes, which close when they can't be damaged.
I disagree about this part. The projectiles of most bosses are either too hard to see or move too fast to reasonably dodge, so it becomes more of an endurance test, than a bullet hell where you need to dodge stuff.
Everything in Terraria is gear based, from DPS to speed and even sometimes health. Your mod includes abilities that functionally ignore equipment, meaning your bosses could theoretically be battled at any time as long as you can do enough damage to be practical. It seems like you also intend the player to be using your mod's mount, which REALLY invalidates the idea that gear matters, because at that point not even movement bonuses are relevant.
The only boss that completely ignores your gear is the final Spirit of Purity Rematch. I mostly made that boss as an afterthought and for fun (since I really enjoy bullet hell), and it definitely is not nearly in the Terraria style in any way. Since it's the final boss, it's assumed you already have the best equipment in the game in order to have defeated all the previous bosses.
Since your bosses don't follow Terraria's internal logic, it's very important to be hugely obvious when you're changing the rules.
I agree here; the biggest offender is probably the Abomination, I'm still trying to think of a way to make that more clear.
If a boss arrives at a DPS cap and can not take additional damage, you should include an animation, like a barrier or some magical effect, to indicate the change. I notice text pops up during the Spirit of Chaos, but a visual indicator will help make it more obvious.
I really like your idea here. Text actually pops up during every boss with a DPS cap, but a barrier-type effect would be so much better. I'll try to include that in the next update.
I'm not sure what's wrong with the Abomination, but when a using a ranger character it seemed to take very little damage. I think I spent at least fifteen minutes floating around hell gently batting its health away. Someone in this thread suggested you had to be within the white sphere to deal damage properly, but that definitely wasn't indicated. If that's the case, remove that and make it possible to damage the boss from any range. There is no visual way to clearly tell the player that's how that works, so including it as a mechanic is just frustrating design. I HATED this boss because of how long its battle dragged on.
The only reason the Abomination fight is challenging is that you need to fight it while in between everything, so I definitely won't be removing that mechanic. I do definitely need to do a better job indicating how to damage it though (I've been stuck on this for a while).
I notice the Spirit of Chaos has a move where the entire screen flashes white and I die. Flavor text did appear, but I'd have to do a bit of testing to discern what the flavor text means. Please don't include unavoidable attacks. They're very cheesy and not any fun. In theory, I suspect I was supposed to stop attacking the boss when its flavor text arose - though I could be wrong because it is not clear - but in that case there are too many AoE attacks or summons and there's no way for me to avert the attack.
I thought the flavor text ("A protective sphere of white light has appeared") made it clear that the white sphere of light could protect you. I'm not sure what else I could do though; do you have any ideas? I've tried to make sparkling white spheres appear good throughout the mod (both for the Abomination and Spirit of Chaos). I agree that unavoidable attacks are not fun at all, which is why I will never ever add those; I enjoy dodging things, and I always need things to be possible to dodge.
Please don't give bosses the ability to attack a player after their health reaches zero. Fool me once, shame on you. I don't appreciate getting to the end of a boss just to get sucker-punched by a surprise last hit. I didn't fall for it twice, so the shame remains on you.
Probably bad design on my part, but I just wanted to be evil here
Aside from that, the mod takes a related yet novel approach. The DPS cap will ensure good equipment can't make your bosses easier, which is arguably not in the proper spirit of the game, but the rewards are very powerful and there's pros and cons to this. It's good work, and I think it would be a lot more fun if you focus any future work on making the bosses more intuitive to the naked eye and basic logic. It's not that anyone's stupid, strictly speaking, but the boss fights put a person under pressure and it's hard to be calm and analytical with minor clues - and I often can't leave my eyes on a written sentence long enough to draw much from it when I'm trying to dodge a spinning laser.
Thanks for the feedback! I will put my best efforts into trying to make things more clear in the next update.
Also - and this isn't important, but it's worth thinking about - do you think that including DPS caps and other "anti-cheese" methods in your bosses makes them internally pointless? The spirit of chaos is post-Moonlord, so if we assume your mod is the only one I'm using, what's the point in beating him twice? He'll be just as hard the second time, and none of his or any of this mod's drops will make your bosses easier to battle. It's like I'm not even getting a reward unless I play Calamity and haven't beaten Yharon yet.
The anti-cheese methods are only really internally-pointless for the final Spirit of Purity Rematch. The DPS caps have been chosen so that you can't reasonably reach them if you're only using this mod. Even with the upgrades from the boss drops, you shouldn't be reaching the DPS cap. It's mostly to protect the end-game bosses from being absolutely destroyed by gear from other mods.
Another thought: don't fill the background with particles that look like enemy attacks. It's so hard to use my eyes to understand anything during the Spirit of Chaos. That boss could use a lot of polish and cleaning. It second phase also sucks to play, because I'm stuck waiting for it to take any actions and the whole battle is confusing enough as it is.
That's another thing I want to work on. I plan to teach myself about filters so I can fill the background with proper effects rather than confusing objects.
on your mods).
since drew fked off from working on calamity there's not really a bossing mod to look forward to unless i make it myself and if i did that no one would want to play it, and i'd have done em all already as i made em! 
i didn't record this one since it like triples the time to go through it (maybe that's why it felt so short) but yeah... hope to see more.
