i honestly think this is a great idea, although some items like the backpack may be a little broken in terms of balancing, and the ender backpack would ruin progression because /echest is a thing for higher ranks, but otherwise there are a ton of great things omitted in the form of slimefun that craftlords uses, like the explosive pickaxe. i wouldnt say add all of the items, just the other ones that wouldnt have to be removed for balancing
The items removed were removed for a reason/glitchy. A good thing to note is slimefun died 2 tears ago. There compatibility has been dying since. If you have a specific request for an item i can check but overall i think most things will stay the same.