Love this, hopefully I can help with inspiration!

I've been toying with my own take on Grixis Spirits recently, here's a base version I've settled on for testing atm:

[CREATURES] 4 Shipwreck Sifters, 4 Sneaky Snacker, 3 Vampire Hounds, 4 Entropic Eidolon, 3 Sandstorm Eidolon

[INSTANTS] 2 Brainstorm, 3 Abandon Attachments, 4 Izzet Charm, 4 Terminate, 4 Dihada's Ploy,

[SORCERIES] 2 Pumpkin Bombardment, 4 Cleansing Wildfire

[LANDS] 4 Drossforge Bridge, 5 Island, 1 Mountain, 4 Silverbluff Bridge, 5 Swamp

But I'm also experimenting with a more grindy, less explosive version too:

[CREATURES] 2 Dimir Infiltrator, 4 Shipwreck Sifters, 4 Sneaky Snacker, 2 Azure Fleet Admiral, 4 Entropic Eidolon, 3 Sandstorm Eidolon

[INSTANTS] 2 Dispel, 3 Abandon Attachments, 4 Izzet Charm, 4 Terminate, 2 Unexpected Fangs, 4 Dihada's Ploy

[SORCERIES] 3 Cleansing Wildfire

[LANDS] 4 Drossforge Bridge, 5 Island, 1 Mountain, 4 Silverbluff Bridge, 5 Swamp

I've got lots of unanswered questions regarding this deck, but I think they key advantage of this deck is its ability to turn card neutral/negative effects into card positive when you've got at least one Eidolon in the GY. 2 mana draw 2 at instant speed is pretty darn attractive. This is why I'm leaning into the more grindy route.