I don't really see this. I mean, Polearm Master + Great Weapon Master is awesome, but for warriors and they get this proficiency anyway.
Feats are not the only thing that is interesting on weapons ...
We dont really know what kind of items will Larian do.
There are items with Lightning charges, Momentum, or Wrath effects ...
There are also items that allows you to deal additional damage, or gain other bonuses ...
And we cant really forget about weapons skills ...
I mean, all people see is just dices ... just ask around what weapon in EA is strongest.
- Many people will tell you its Everburning Blade ...
- Those who dont despite Dip ... will claim its either Blade of Justice, or Sussur Greatsword ...
- People with Wrath build ... will claim its either Githyanki Greatsword, or Blooded Greataxe ...
- While in fact, its Light of Creation.

Any other class can already pick up a quarterstaff and wouldn't pick those feats ever.
I dont see how is this relevant.
I think, maybe getting the reach of a halberd on a monk would be fun, but now he has to be strong to use it properly.
Has they tho?
Thats the question we dont know answer to ...
I mean, in PnP its clearly stated that no Heavy or Two-Handed weapon can be used as Monk Weapon ... but will Larian respect this?
Also, I think the items he named aren't necesarily weapons;
Well, obviously.
But as we speculate about usages of proficiencies to certain weapons, it seems quite logical to concider weapons.

Specificly ... those weapons.
Think of the amulet that sets your INT to a flat out 17. This allows you to start dipping into wizard, or respeccing and dumping all your int points.
Its a crown.
But yes, there are certainly other items.