Draconic powers

I've been thinking about what kind of powers the dragon soul provides for the character and how it ties into the gameplay and progression. The simplest answer would be superhuman stats like strength and agility, but I also want something more iconic and impactful, like how the Dragonborn character in Skyrim can learn dragon shouts for example.

The idea I'm exploring is a kind of unique draconic magic based on dragonfire, where the human part can magically siphon fire from the dragon and shape it into various fire spells. For example, imbuing their weapon with fire, incinerating objects at will, summoning walls of fire or simply casting fire from the tip of their fingers. Since the fire is derived from the dragon, it will also inherit all of its properties (like fire color and fire upgrades), and use the same "fuel tank" as regular fire breathing that empties when breathing/casting fire and refills over time.

These fire spells would add a lot of variety to combat/battles and let the rider participate more actively instead of just sitting there while the dragon does all the work. Perhaps you could switch between controlling the dragon and controlling the rider, letting the dragon fly autonomously when you control the rider so you can focus on hitting things with the fire spells.

The draconic fire magic needs to be very strong to be a viable alternative to simply breathing fire when flying, which might be an issue for when/if dismounted combat is added because those engagements would usually be on a smaller scale, like a dungeon with maybe 10 enemies at a time. A potential solution to this that makes a lot of sense is that the powers depend on how physically close the dragon and rider are, so when you are mounted they are at their strongest and you can sling fire balls that blow up walls and decimate regiments, while if you dismount to delve into a dungeon without the dragon, then the powers wane to a more suitable level for that scale.