I don't find Gale very suspicious either. He seems to be very honest about everything so far. I can see his story taking a darker turn, when Mystra gets involved ( and she most certainly will be) and you make the wrong decision. But I don't think, he is evil atm. or suspicious in any way. He is certainly one of the more easygoing companions for me. He and Shadowheart are the comps, I get approval easily by just playing how I like. Given that all companions are basically Mary Sues, who are oh so special, I can totally see the Elminster route for Gale. I wouldn't care for it, but I wouldn't put it past Larian.
About the Dragon Age comparison: There are no real similarities between Gale and Solas apart from the fact, that they are mages. Gale is open minded and friendly, while Solas is borderline racist ( try talking to him as a dwarf or Qunari). Also Solas betrayal isn't really a surprise, If you played the first two games: in every game, you are played by your mage companions- Morrigan in DAO, Anders (and bloodmage Merrill to an extent) in DA2 , so yeah, I was eying Solas, Dorian and Vivienne very suspicious.
Apart from the similarity of mages, Gale studies the weave and Netherese magic just like how Solas studies the Fade and Rift magic. I don't see him as racist towards the Dwarf and Qunari, they are not known to be nice races. Solas is an Elf, let alone he's practically a God Elf, Fen'Harel. Elves in Dragon Age are seen as slaves minus Dalish Elves in the wilderness. For example, if you choose to be an Elf, you have markings on your face. You character thinks it's a Dalish thing until Solas tells you it's not. Solas isn't seen as evil by fans but definitely manipulative. He did what he did because he thinks it's best for his people but still he's messed up for what he did and he pretended with you the whole time. There is a possible similarity with Gale, he loves Mystra and wants her approval. It's possible that he's lying to you about who or what he is just so that he can continue to please Mystra and be the most powerful wizard in Faerun. That's where Gale possibly being Elminster comes in. He does say he's a "Chosen" of Mystra just like Elminster.
