The Cubs picked him up off the scrap heap and he did well for them. .265/.346/.447 with a 10.4% walk rate and 18.7% K rate. He's not a great defender.
Not a great defender but decent power and he's good at getting on base. Reliable bench help is hard to find; I think the Cubs will miss him. (And they could have gotten so much more than a junkerball pitcher.)
As far as a Soler trade, that's been talked about all offseason and even last season. If they could get a good starting pitcher (Tyson Ross was frequently mentioned), it could still happen.
I don't think the plan is to trade Soler if they already dumped Coghlan. He'll play off the bench and start in left on days when the Kyle Schwarber Experience is behind the plate.