Firstly, as a solo campaign, 'balance' isn't so much of an issue. If she wants to play a fire Druid, making a fire Druid even roughly in line with the standard classes is fine.
Secondly, the actual details of your circle. The only big thing I can see is Fireball - but the Light Cleric gets that anyway. You're swapping domain features like damage for the Druid's nature abilities and the weak wild shape. It's about even.
Having cure wounds for a solo isn't that much: you're only getting one action per turn. Is it the best thing you can do in that turn? Certainly for a solo PC it's not too much.
Slightly aside I would advise for a solo campaign that a beastmaster archetype or at least having a familiar. I've run solo for my brother before, without a group, many encounters (of the straight-up standard fight) are basically luck or attrition, far more so than in a group.
Only those where the PC approaches something with many non-fighting options (sneaking, distracting, bluffing etc.) are not foregone conclusions. Your druid having options such as summoning is a pretty good choice for solo.
Beastmaster, familiar, summoner, anything with more 'boots on the ground' gives plenty of options, which is far more important in solo than in group, so summoning for this custom circle is especially nice for solo