Maybe we are hopeful, but I want to disagree with you. I think X-Men fans are plentiful enough and, especially with the high-profile revival of the animated show which is presumably adapting the storyline we receive minimates of (topical, anyone?), likely to be interested in some merchandising.
Zach said it includes an obscure X-Villain. Is Goblin Queen obscure? I don't think she is. I feel like X-Men fans and even general Marvel comics lovers know about Goblin Queen. It might be safe to assume that the villain in question is either N'astirh or the easier-to-engineer S'ym. That in mind, I could see four of the five slots being filled thusly:
Goblin Queen with baby Nathan.
Mister Sinister
S'ym/N'astirh
Magik
Who takes the last spot? You choose. It could be Colossus, or a Wolverine variant, or another New Mutant, maybe Havok as Goblin Prince if we're getting wild. But, we received Cyclops and Jean in the costumes they wore during this story not too long ago and they are still somewhat readily available.
Hopeful? Yes. Unrealistic? No.