Now, there are a few things about these tables. First off, they are designed for a specific campaign setting, not for general use, and conform to generally used technology within that setting. This technology does not conform to a real world technology level, but to a made up fantasy one. Particularly heavy armors such as full plate have never really been common in world, but maintaining game balance was a concern, which is why armors were moved up in category so that some medium armors could gain the stats of heavy armors. Full plate doesn't exist, but you can get the same stats with a breastplate. Making quilted cloth about as good as leather used to be was also something I wanted to do, because I do think quilted cloth looks cool. The greatsword got renamed because it evokes visions of a big, heavy sword like a zweihander, which is a weapon that isn't used in my setting. Two handed swords are known of, but they aren't that big. So, longsword takes the place of the greatsword, and arming sword takes up the 1d8 one handed sword role. Bastard swords don't exist, but a trait can be taken to learn to wield a longsword one handed for 1d10 damage (feat isn't worth it). I feel this better emphasizes what two handed swords are like in my setting - they aren't overly big swords, and they can be wielded one handed with some training.
The whole polearm being able to choose whether to have reach thing is meant to add versatility and desirability to the weapons and reflect the fact that the lengths can very quite a bit, and the reach shortspears reflect warriors who'd wield very lengthy spears one handed.
I wanted to add a couple finessable slashing weapons (slashing Swashbuckler shouldn't require any more feat expenditure than piercing Swashbuckler), and scimitar was an obvious choice, since it has identical stats to the rapier aside from being a slashing weapon, and it makes thematic sense to wield a scimitar with blinding speed. After watching many Chinese action movies, I came to the conclusion that spears should be finessable and monk weapons, because the spear moves in those movies are awesome and I want them in my games. In fact, the light spear exists purely to emulate those movies whilst being mechanically viable, because I don't really know of any real world equivalent.
That whole recurve bow thing was because nobody uses shortbows, and longbows conjure up images of a very specific thing to me. The composite bow thing is because I don't run games below 4th level, so everybody has composite anyway. Firearms are common enough in my setting to be martial.
Contact between "European" and "Asian" peoples has been going on for centuries, and a lot of the adventures take place in areas like "California" or "Australia" where people from both areas are present in large numbers, so both Western and Eastern equipment is commonly available. I do plan to add "African" and "American" weapons at some point.
Do I have a good selection going, or does this just sort of fall flat? Any mechanical changes that cause issue (most weapons don't have mechanical changes, but those that do are often main weapons)? Also, anything seem like an error? I just fixed the rapier (it was listed as slashing when it should have been piercing)? Might have other errors.
Not sure what kind of feedback you want. I've looked over your charts and noted the similarities and differences. That's an awful lot of work for rather small changes. Your players will need to invest some extra time learning and considering your non-standard weapon tables.
How confusing is it?
Regarding spears, and their portrayal in cinema, I think you mistake skill for agility. The spear has historically been the primary weapon of warfare, most of the world over, through most of recorded history. This is because it works well [Youtube spear sparring videos]. It requires strength and skill to use a spear effectively. This martial artist suggests the spear is not a particularly finesse-able weapon, rather that's just what competent spear combat looks like to the unschooled eye.
I'm not so much going for realism as cool and it making spear combat as viable as longsword combat. I mean, IRL, a rapier isn't as agile as is portrayed in D&D.
I totally agree with you that all spears should be monk weapons. Do a youtube search for 'Shao Lin spear', if you need clarification as to why. Failing to give monks proficiency with the long spear (or any reach weapon) is just silly, and probably a holdover from AD&D version 1, which made the same mistake but no one cared because back then the spear was a lousy weapon.
Well, that's fixed now, and I have seen some cool things done with really long spears.