[Phanx]

Added:

• in yellow: hints at the bottom of the tooltip that span all 3 cells,
• in pink: item counts instead of just "No" for not-yet-completed quests, with quests that are ready to turn in no longer highlighted in red,
• in green: auto-switching back to showing completed quests once all quests have been completed (you might want to use a second variable for this so as not to mess with the saved variable, or just take it out).

tooltip:AddHeader(TILLERS, ITEMS, COMPLETE)
local line
for i = 1, #npcs do
	local npc = npcs[i]
	if not npc.item then
		npc.item = GetItemInfo(npc.itemID)
	end
	if not IsQuestFlaggedCompleted(npc.questID) then
		-- note "line" is no longer local to this scope!
		local count = GetItemCount(npc.itemID)
		line = tooltip:AddLine(npc.name, npc.item, format("%d/%d", count, 5))
		if count < 5 then
			tooltip:SetLineColor(line, 1, 0.1, 0.1, 0.3)
		end
	elseif not hideComplete then
		line = tooltip:AddLine(npc.name, npc.item, YES)
		tooltip:SetLineColor(line, 0.1, 1, 0.1, 0.3)
	end
end

if not line then
	hideComplete = nil
	self:GetScript("OnLeave")(self)
	return self:GetScript("OnEnter")(self)
end

line = tooltip:AddLine(" ") -- blank line

line = tooltip:AddLine(" ")
tooltip:SetCell(line, 1, NORMAL_FONT_COLOR_CODE .. L.CLICK_SORT, "LEFT", 3)

line = tooltip:AddLine(" ")
tooltip:SetCell(line, 1, NORMAL_FONT_COLOR_CODE .. L.SHIFT_DOWN, "LEFT", 3)

tooltip:SmartAnchorTo(self)
tooltip:Show()