dont know, an injured and playing poorly Ryan O'Reilly got the same package alone last yr, Henrique is playing pretty amazing right now, so I think its a bit light for Henrique, let alone theres nothing there for Lyub and the retention on him.

much better prospect than Holmberg is needed, (Voit, Niemala, Hirvonen?) and maybe another pick (a 5th)

I think for the Leafs that is not a deal I would like to see happen. Maybe break it up a bit.
A 5th for Lyubuskin would be ok but he does not bring much to the Leafs.

I don't think Henrique will make that much of a difference that offsets the loss of a late 1st rounder in a draft year deep in D men.
The Leafs real need is a RD who can play with Rielly so if they are going to trade that 1st it needs to maximize the return on that RD.

As the reliable @Hammerwise says, substitute Niemela for Holmberg (Anaheim has plenty of forward prospects already) and the Ducks would take that offer.