The list I've been tinkering with ever since support was announced. Made before the world premiere starter, I'll have to test to see if it's worth it as the deck is already relatively engine-heavy. Can pretty routinely stop combo decks when going first, and without interruption there are 7 (9 including Thrust) one-card starters ending on Statues Game (Staring Contest is a 1.5 card combo).
The goal is to summon Melffy of the Forest turn 1 to search Statues Game (remember, not once per turn! If it gets Ashed, just activate another from hand), or failing that, having enough Melffys in hand to put up a few disruptions. Puppy generally goes into Kalantosa, and Catty searches either Hop-Ear or Pinny, whichever you don't have in hand. This lets you quick-synchro into either Merry Melffys, Locusts (then into Diabell or Accel), Silvera, or directly into a Level 8. Accel target is currently B2B due to synchro decks dominating the meta at the moment (plus I found it funny that it's generic), but any generic Level 10 will work.
Don't sleep on Staring Contest, the start of battle effect has genuinely saved me more than once. Hide-and-Seek is there for grind and for things like Blitzclique and FnV package. Tag is an alright card, but I decided it wasn't worth bloating the deck with it.
Non-engine is built around going second, as Melffy sucks playing into a full board. Side decks are always finicky, so my current one is a mix of going first non-engine and tailored going second non-engine. Alpha can honestly work going first or second, it's both good for Turn 3 and as a breaker.