Hey
@DivermanSam and co. I was wondering if you would be willing to take some suggestions for some additional accessories to re-balance Melee. I'm currently attempting a Boomerang-only playthrough in Expert mode, which I thought would be fun considering the Boomerang love this mod brings. And, while it is fun, it brings to my attention a key issue with Melee today: Yo-yo's reign supreme. While other classes have their "best weapon type" move and change over the course of the game, Melee players basically switch to the next-best yo-yo. They even have their own accessory progression line specifically dedicated to yo-yo's.
So, my suggestion would be to consider adding in boomerang-specific, flail-specific, spear-specific, etc. accessories and equipment to make melee more of a choice-friendly class. If I'm crazy, feel free to tell me. I just had to get this off my chest.
That's really hard to balance for multiple reasons over several layers. I'm not exactly disagreeing with you, but rather laying out a few notes on why messing with this too much could make an even bigger problem than the one it solves;
A. Expert mode is very poor for balance in general. In Normal mode, you can use normal broadswords and spears dedicatedly. Any boss in the entire game can be rather easily taken out with smart positioning and a lance, even though it's harder than most ranged options. In Expert, this ALL goes out the window and it seems to be absolutely intentional. One needs to look no further than Eye of Cthulhu, who goes from a boss who leaves the option open to jump and hit him with a sword, to a total spaz whom you could only cut by total accident. Things do too much damage to make close range combat anything but suicide. Expert mode by default will limit the player, and if you make items to mitigate that, they become too good when combined with the existing options.
B. Reiterating above, if you make some accessory like "melee damage penetrates 50 defense" to make spears and the like more practical, they also make yo yos more powerful too, and nothing has changed. If you make armor to soak up more damage point blank, then yoyoers/rangers can use it even better by taking even less damage than before.
C. not every weapon has to be practical in every situation. There's weapons that are very clearly meant for exploration, and some for boss killing. Boomerangs for instance shine in their knockback stat, something bosses don't care about, so they see much more use against general mobs than a boss fight. This might just be something you sometimes have to accept, especially on Expert, because making every weapon fit every role will upset how they all stack up against each other and then something else is suddenly super OP.
and D. is just that when something sticks out as unbalanced, most of the time, you want to change that one thing, instead of everything around it. I've had a grudge for yoyos since their introduction for reasons very similarly to your's. They're too versatile. No real reason to use other melee weapons. That's on them, though. Yoyos are OP. The answer isn't to make everything else OP with them, but to bring yoyos down to everything else's level, and this is something a mod like Thorium should avoid and leave to a standalone mod instead. If you bring all the other melee weapons up, then problems happen. Swords, which used to be decent for normal mobs but bad for bosses, becomes decent at bosses and ridiculously good for normal mobs. Spears become DPS kings that will likely kill things just by facetanking them. Boomerangs start to outclass ranged weapons in nearly everyway, featuring awesome crowd control and similar single target DPS suited for taking on bosses. It's all so very fragile.
TLDR version of everything I just said basically boils down to, be careful what you wish for. It's way to easy to make a different weapon type "the next yoyo" if you change their dynamic too much. The most graceful solution to your problem is honestly to just swallow your pride and go to Normal mode, use Boss Expertise for their upgrades. Expert isn't suited to something like this. Expert destroys a lot of the game balance just by itself.