I actually prefer Spellbender to Counterspell. It usually stays on the board longer so I can use it for Secret synergies. They always expect Counterspell and forget Spellbender exists. I've caught Blessing of Kings, Pyroblast, even Mind Control with it. Though that's probably because I'm low rank.

Ice Barrier is another nice Secret for staying on the board, if all my secrets trigger immediately on the next turn then I can't use Valet, Arcanist, etc.

I use Faceless with Polymorph to "mind control" a minion or push my advantage when I have Medivh or a buffed up Ethereal Arcanist. Also taking enemy Ragnaros and having him immediately kill the other one is fun. (I'll probably take out Faceless and Burglebot though)

Medivh is a bit cheese, but he works well with most cards in my deck, especially Kabal Lackey. I play Medivh, then Kabal Lackey into a Secret to summon a 3-drop. Then Flamestrike the next turn if I have it. If Babbling Book gives me a high cost spell then I sometimes save it for Medivh as well.