I don't think completely removing Tracker's Knife is a good long-term solution - it needs to come back in some way, shape or form.
The difference in availability of wards between Warding Totem and Tracker's Knife is too large and I think that this could bridge the gap a little bit.
Binding the Reduced Cooldown to Machete/Talisman as opposed to Smite means that someone can't just switch their Summoner Spell with Unsealed Spellbook to get free wards - they would actually have to invest 350g if they really wanted the Passive.
