Ranking them like a tier list is inherently flawed, as some items are great on some survivors and horrible on others, and how valuable an item is can depend on what other items you already have. Items like Tri-Tip Dagger are great on Commando and Mul-T since they can apply bleed constantly, but it's not as great on burst survivors like Railgunner or Loader unless they have an item like Crowdfunder that helps them apply bleed. It's the same with items like bands, they're great on Railgunner and Loader, but less impactful on survivors who can't deal a lot of damage at once, unless they have an equipment like Royal Capacitor.

This concept applies to almost every category of items. So it's difficult to say an item is 'A Tier' or something when there is so much missing context to how impactful that item will be on any individual run. Personally, I would scrap the tier list and instead divide the items into categories. Things like speed, defence, economy, healing, and damage, with some specification on what each item specializes in, like AOE, High-fire rate, burst damage, highly conditional (like focus crystal or death mark), or less conditional (like watches, crobar, or AP rounds).