Duskblade is broken.

I don't find it broken tbh,

The problem with duskblade I found is how ridiculous expensive it's craft items are. You can do a back for a dirk, which wouldn't be different from trying to be a yuumuu's or something... but the BF sword is actually pretty gold killing. Assassin don't really have a use for the BF sword since it doesn't have a passive of any kind and cost more than your usual items with a passive. Why would I want to back for a 1300 no passive item when I could instead finish boots, hydra, or something cheaper and easier to path? Something that will actually help my clear speed or get my abilities soon rather than just damage.

I found building duskblade as your last item is imo the best build path, because rushing it early on with no cooldown reductions, armor pens, or active like the build paths for yuumuus, hydra, even black cleaver just puts you a little behind early on... it's an item ment for assassins doing well and being able to rush it easily without sacrificing anything, not as a "go to item" inorder to make the assassin op.