As somebody who plays a red-blue EDH, using card drawing, spell slinging and converted mana cost shenanigans to my advantage. I have some suggestions. For creatures that can allow you to draw cards, I suggest using Arcanis, The Omnipotent. He can tap to allow you to draw 3 cards. He is a six-drop for a 3/4. But whatever. Another suggested creature is
Nin, The Pain Artist. He is a 1/1 with the ability;
X, UR -
Nin, The Pain Artist deals x damage to target creature. It's controller draws that many cards.
Combine that with
Chasm skulker, a 1/1 creature which gets +1/+1 counters every time you draw a card.
Other cards, like
Thought Reflection do wonders for draw decks too, As does the new
Monastery Siege enchantment. Something else to consider, if you're not caring about other players drawing cards too, some old artifacts such as
howling mine and/or
font of mythos are absolutely legendary for drawing cards. By the way, if you plan on creating this draw deck, I also suggest an artifact such as
Spellbook. It's a zero drop artifact which gives you unlimited hand size. I also suggest the land
Reliquary Tower.
In manner of return spells, I highly suggest cards such
Mystic Retrieval, which allows you to return an insstant or sorcery for 4 mana. However, it has flashback for 2 and a red.
Volcanic Vision is also a good return, as it allows you to have that little bit of burn on the side. However, I am playing a deck which lets me cast these for cheaper, so I apologize if they don't seem as appealing for you. Also, Charmbreaker Devil's are a great way to return some instants and sorceries while dealing lots of damage. Another great one is
Mizzix's Mastery. It doesn't so much let you return spells, instead it let's you cast them from the graveyard and then
exile them. It costs 3 and a red. Not to mention it has
overload for 5 and 3 red. Also, another perfect card for a return deck, is
past in flames. It gives every and all of your instants and sorceries in the graveyard flashback, where the flashback cost is equal to it's converted mana cost.