instead of steven's, if you're running a dark deck, you could use rocket's mission or tvr...for celio's network, once again, if using dark, use rocket's pokeball, if not, use master ball or waly's (whatever you like best)
I personally would go Rockets Mission>Stevns anyway because you coulde always use a Rockets Mission...While you can rarely use Steven...Draw 6...Then next turn Draw a nother 6 Via Stevens...
Depending on your deck-
Draw cards- Cosmo, Prof Birch or Copycats.
For Poke search- Dual ball (draw back is a flip and can only get basics), Great Ball, Lanette's search
Again these all don't work in every deck- you've gotta deceide your makeup and see what works best.