There are a couple variations that can be made with the free blue/green deck. The deck can be highly creature oriented or creature control heavy.
Cards that specialize in a theme (rouges and wolves) should be culled out, since the deck would be hard pressed to carry any specific creature theme. Taking out Nimble Dagger and Llanowar Charm right away.
Keeping the efficient creatures, creature enchantments, and spells, the deck starts to take shape:
Obsidian Golem x3
Sentry Rogue X2
Swashbuckler x3
Aura Finesse x1
Inspiration x3
Time Ebb x3
Unsummon x3
Elvish Warrior x3
Llanowar Elf x3
Lone Wolf x2
Pathfinder x4
Elvish Agility x3
Giant Growth x3
Oakenform x3
Plummet x1
This selection gives 40 cards to try the deck.
Variation example
Some of the less efficient creatures (Obsidian Golem and Sentry Rogue) can be switched out for more creature control cards (Entangling Vines, Plummet and/or Surgical Precision) or better cards from the free booster.
Of course, this is just one deck idea and the deck can either be a green deck with a few blue cards thrown in or vice-verse.
Complete blue/green list