This feels like a much-needed supplement that provides players and DMs with a way to scale up their starting equipment rather than just throwing away your prized possessions when something with a slightly bigger number comes along. It's a way to incorporate magic items into your game, without players necessarily finding a Flametongue in the belly of a wolf, or a Giant with +3 armour too small for it. It also feels like this should almost be a prerequisite for some classes and archetypes (Kensai, Path of the Ancestral Guardian, Hexblade Pact, and College of Lore all being quick examples that come to mind). I do also like that this exists as an alternative option for constructing magic items to add variety to the options in the DMG.
The only area where I feel like this supplement is lacking is in the depth of options from a non-combat perspective. While I realize that this is kind of the point of weapons, it would have been nice to see more variety in terms of options for things like non-combat encounters, dialogue, travelling, etc. But as I mentioned in the beginning, this supplement was well worth the investment!