A Druid Circle Based on Forest Fires and Regrowth: is this balanced with Land Circle Druids?

Inspired by a question by Stephanos and tempered by the PEACH process at GiTP, I am asking for a comparison to Circle of the Land druid sub classes for this Druid proposed sub class, homebrew, since my answer to Stephanos just didn’t satisfy me. As with Stephanos’ idea, this sub class combines a raw fire elemental focus with an increase on melee engagement by the Druid, but it does not benefit from the spell recovery feature of other Land Circle druids. Is it balanced, or underpowered, as compared to the Land Circle druid sub classes? It also does not try to do as much as the other model in terms of using XGTE spells.

Circle of Flame

Fire burns the forest. Out of the ashes comes new growth. Druids who choose the Circle of Flame balance between destruction and regrowth. Wind spreads forest fires, cleansing a greater area. Lightning starts forest fires when it strikes a dead tree. From fiery death grow new beginnings. Druids in the Circle of Flame believe that everything will burn one day, to be re-born again.

Circle of Flame spells (always prepared)

at level 3 Scorching Ray, Gust of Wind
at level 5 Revivify, Lightning Bolt
at level 7 Grasping Vine, Fire Shield
at level 9 Control Winds, Flame Strike

Only You

When you choose the Circle of Flame at level 2, you gain the fire bolt cantrip.

Heart of the Flame

At 2nd level, as an action, you can expend a use of your Wild Shape feature to awaken the primordial spirits of Fire rather than transforming into a beast form. While this feature is active, you gain the following benefits:

  • Add your Wisdom Modifier to your AC

  • Add Fire damage equal to your Wisdom modifier to your melee attacks

  • You can use your reaction to heal yourself, or an allied creature within 10 feet of you, for 1d4 hit points. This healing increases to 1d6 at 5th level, 1d8 at 11th level, and 1d10 at 13th level.

    These effects last for 1 minute, or until you are reduced to 0 hit points.

Heat of Battle

Starting at level 6, the druid gets an Extra Attack when taking the Attack action.

Flaming Soul

At level 10 you gain resistance to fire damage. While concentrating on a spell that does fire damage, you gain +2 to your armor class.

From the Ashes

Starting level 14, as a reaction, you can absorb fire or lightning damage dealt to yourself, or to a single friendly creature within 30′ of you. You, or the friendly creature (whomever was subjected to the damage) instead heals for the amount of damage taken. This feature refreshes on a short or long rest.

If I have missed the balance point here, where did I miss and by how far?
One of the issues I’ve had with playing druids is that a lot of their spells require concentration. A weakness for this sub class is that by engaging in melee more often than a pure spell caster, the chance of concentration being lost would appear to increase.