Dude...
TAKE OUT DARK GOLBAT/CROBAT.
You have to replace it with HL Crobat.
If you do that, not only in HL Crobat better, but you might've noticed that Golbat evolves into HL Crobat AND Crobat EX, meaning the speed of your deck also increased.
Ditch Wally. And if you want to use Oak's Research, use at LEAST 2. I reccomend about 3, but it's up to you.
Many cards in that deck can be improved, here's a version that me and BlastoiseShellShocker made:
Pokemon - 24
4 x Zubat (HL)
2 x Golbat (HL)
2 x Crobat (HL)
2 x Crobat EX (DX)
2 x Pidgey (FRLG)
1 x Pidgeotto (FRLG)
2 x Pidgeot (FRLG)
2 x Natu (SS)
2 x Xatu (SS)
3 x Dunsparce (SS)
2 x Jirachi (HL)
Trainers - 20
3 x Prof. Oak's Research (FRLG)
2 x Steven's Advice (HL)
3 x Celio's Network (FRLG)
1 x Low Pressure System (DR)
1 x Space Center (DX)
4 x Rare Candy (SS)
2 x Mr. Briney's Compassion (DR)
2 x Swoop! Teleporter (TRR)
2 x Surprise! Time Machine (TRR)
Energy - 16
16 x Grass Energy (RS)
That deck is being worked on, but heres a nice strat that the deck can use:
Turn 1:
Move 1 - Put Dunsparce active
Move 2 - Attach Grass Energy
Move 3 - Strike and Run (Search for Pidgey,Zubat and Jirachi)
Move 4 - "Run" with Jirachi (now Jirachi is active)
Turn 2:
Move 1 - Attach Grass Energy to Jirachi
Move 2 - Either evolve the Pidgey or Zubat to Pidgeotto/Golbat (if you have them in your hand)
Move 3 - Make a Wish (evolve Pidgey to Pidgeotto)
You'll have Pidgeot out searching for cards before you know it using that strat. I reccomend you change a lot of the trainers in the deck..
I also noticed the deck really lacks many basics.