I just won a 14 person store championship with Luke, Leia, 3p0, Gideon on a diplomatic mission, and two elite echoes.
Rebels definitely feel like the stronger competitive side. Top four were all rebels, and three featured the wonder twins. The other had double eEchoes, two rookies, and a eRebel sab.
The difference for me was the eEchoes. I killed two sets of wonder twins because they just tanked so much. They also survived the wookie onslaught due to their defense and range. They also hit harder. Overall, I can't stress how good the eEchoes are.
Additionally, Leia is the most OP card in the game. She should be the first inclusion for any rebel build. Game changer
That has been the Rebel squad that I've been most impressed with so far. The ability to roll Wookiee-dice when up close, and to shoot decently at range, and having a great hp/cost ratio is what makes them really strong.
eSabs just seem too squishy for me, when I'm already putting 18 points into the Wonder Twins.