Been thinking about this for awhile haven't exactly put it in practice yet, i don't get to play much so maybe some more experienced players could give me some advice if it would be a good ideal or not.

The ideal is to make Serena and Raythan have dual archetypes and each of their miniatures represent the archetype, nothing else would change as far as abilities, statics or anything like that. Raythan would be a Warrior/Scout with the hero miniature representing the Warrior and the Lt. miniature the Scout. Serena would be Mage/Healer with the Lt. miniature acting as the Mage and the hero miniature as the Healer.

Anyone else think this ideal could work or would a overhaul need to be made to get the results I want? Thank you.

If you're just talking about using the Raythen and Serena characters as heroes with classes of a different archetype, that's something you can house rule at your leisure. However, I'd suggest that Raythen and Serena are not designed for those classes- their attributes and heroic feats/ abilities lend themselves to scouting and healing, respectively. That being said, I'm sure you can find interesting pairings for them.