How does strategy change between early game and late game in Dragonfire?

The meta flips with the weight of research, which climbs enormously over the seasons.

Early game (weak research, a few %):

• What wins: your dragons' level/stars, auras (Rhysarion −27.5%), green +20% affinity.
• Research and ±7% are minor and comparable.
• Priority: raise your dragons, tend your Center, align affinities.

Late game (research at +1,000% and beyond, up to ×60):

• Research on the troop type you field crushes everything else.
• Priority: max the research for the type your roster carries best, then global Initiative.

In both cases, two constants: multi-wave attrition (the defender never heals) stays the number one factor for taking a target, and the permanent (stars/Habits/Heirlooms) beats the disposable.

The reflex to keep: never weight the layers "by feel". Look at your actual research level and adapt — that's what tells you whether you're in the early or late meta.