Gifting Decks/Balancing

I have a decent collection of cards built up and I want to build some good decks for my friends as Christmas gifts this year so we can all play together. I want to make sure I don't give anyone a deck that's too OP or too underpowered - does anyone have advice on where i can look? I'm still learning the rules of the game and id like to build decks with their favorite characters if possible!