This might have been said enough times: Winmillion needs an upgrade.
The Winmillion is an interesting weapon to use, and is, hands-down, my favourite sword of all time.
But the Spur crafting chain ends at 4 stars, with Winmillion. I believe that it deserves a 5-star upgrade. Increased damage, increased energy disk range, and a new look! Maybe the possible upgrade would look nice in violet or maroon.
Perhaps the entire Spur chain could end up like a new Brandish chain, with varying damages and status effects. Like three possible upgrades can inflict mixed elemental and normal, or pure elemental damage, and inflict either Fire, Freeze, or Shock with the charged attacks, and "built" into the regularly fired energy disks at Tier 3. And one or two Shadow upgrades, with either mixed or pure, could inflict Poison or Curse (WE NEED ANOTHER CURSE WEAPON). A pure normal upgrade could inflict stun with charged attacks, or just a universal upgrade could inflict all status upgrades on charge attack, like the Sealed Sword.
The previous paragraph doesn't need to be brought into consideration; I think a normal damage 5-star upgrade will satisfy the majority of Winmillion users.
You know, sometimes it helps to just search for things. To see if they've already been suggested. Maybe multiple times. Maybe once every two weeks. ¬.¬
And here's one you might not find by searching, but has the best suggestion in my opinion. Go there and read everything about the Spur line.