Deck Building starts with the characters, I am probably going to say that some combinations will be better than others, if the game design is tight we could see a good number of combinations work.

There is a few interesting trade offs happening here in the characters you are going to chose.

Firstly the Elite Version comes with an extra dice, which improves the probabilities of rolling a key face on the dice and also gives you the advantage of perhaps rolling the same key face on both dice. The trade off here is that the Elite version has the same health as the untrained version and thus your team of characters will have less overall health.

Secondly the characters colours allow you to add cards of that colour to your deck. This to me is the most interesting of the problems the game ask you to solve. If you take a mono colour team you can pretty much consider each card of that colour for your deck. With a two colour team you can take a greater variety of cards, but must consider the use of "Spot" cards. A three colour deck is also quite possible, but you would have to include any "Spot" cards only where they have been well considered.

This will also be affected by the cost and availability of each character type, which in Awakenings we may not have the depth of choice as we will as they add sets.

I would look at the various battlefields next, I think your choice of characters will provide a "rough archetype" that you will build towards. So you are looking at taking a card that will synergies with your choices, while giving your opponent only a slight advantage.

Now build the deck: Start with 18-20 single cards that look like they will work with the 2 characters, then duplicate 10-12 of those cards. I feel that there may be a bit of a "rule of thumb" here as to how many events, upgrades and support a deck can support. But until I get a lot more deck building practice I just can't make a suggestion as to where to start here. This may also be adjusted as to card cost and resource generation.

I think one consideration that remains, is just what you think if your key character and how do you plan to obfuscate (hide) that during the first turn or two and how you can enhance that characters chance of doing well.

The game is far more about how you play and the choices you allow yourself and how you read your opponents options and choices. So if your opponent takes the two shields at the start of the game, what can you learn about his choice to put them both on Ackbar for example? What if you have a bad roll, can you bluff and bluster your way through a bad turn.

That all that said creativity and experimentation could be worth far more than just netdecking, so if an idea for a deck looks interesting or just fun, give it a go. Failure is a better teacher than success, and you'll see far more of the choices and options each of your opponents can have for playing more and varied games.