ideas for harpie deck

Is this on DN or IRL?

On DN
Though if you could give me ideas of what to put in my real deck since I have two decks I want to combine that be great

Harpie builds like to focus on Xyz summoning, and need to be very consistent to do so properly. The build you have here has a lot of clashing strategies and can be overall slow.

-2 Birdface (Really slow)
-3 Girl (Only useful with Rabbit)
-1 Lady 1 (Dead space, and pointless at 1)
-3 Sisters (Not useful in a regular Harpie deck)
-3 Baby Dragon (Not useful)
-3 Brother (Only usable with Rabbit)

-3 Shield (Not useful)
-1 Egotist (Only need 1 of these)
-3 Triangle (Not important enough to be at 3)
-1 Double (Don't need it)
-1 Solidarity (Don't need it)

-1 Radiant MF (Not worth the space)
-1 Eyes (Shouldn't be used anyways)
-2 Trap Hole (Bad in this format)
-1 Jammer (Bad/outclassed)

+3 Channeler (Really important in Xyz builds)
+3 Dancer (Really helps consistency)
+2 Battlestorm (Good control)
+1 Gale (Easy sync, but not a huge part of the deck)
+1 Zephyros (Easier Xyz)
+1 Dark Simorgh (Useful card)

+1 Dark Hole (Important)
+2 Forbidden Lance (Priceless in here)
+3 Hysteric Sign (Can pull Egotist whenever, and extremely good card in general)

+2 Icarus Attack (Staple for any Winged-Beast decks)
+1 Solemn Judgment (Staple)
+1 Solemn Warning (Staple)
+2 Bottomless (Pretty good)

Just a start. If I'm not mistaken, that should bring it down to 40 or 41 cards.

As for your side, a decent setup for Harpies given the changes I've made to this deck could be Veiler, Duality, some staple traps like D-Pris, Compulsory, a third Icarus, Torrential, and Starlight paired with Stardust. Harpies these days are really focusing more on easy Xyz. Another possible card you could use is Quill Pen. It's like a mini Avarice. You CAN side MST if you want, but this deck already has a ton of control, so it isn't necessary. Book of Moon is also pretty good as utility.

As for your Extra, a pretty good all-around setup with my changes could be:

1 Faerie
1 Armor Master
1 Black Rose
1 Mirage Dragon
2 Chidori
1 Maestroke
1 Dragoss
1 Big Eye
1 Shock Master
1 Utopia
1 Corn
1 Papill
1 Sylphine

A common play is to use Channeler to Special Summon Pet Dragon, making Channeler become Level 7, then Xyz'ing for Big Eye or Dragoss.