Is this Bo'tirnan homebrew race balanced?

Question

The Bo'tirnan are a race born from the fallen branches and fruit of the tree of life. At the beginning of their lives, the Bo'tirnan resemble humans with tough, bark-like skin and wild leafy hair. As they age, they appear to become more and more like trees, growing branches and root-like limbs. They usually live in great colonies surrounding an ancient of their race, whose age has transformed him into a great demigod of the forest.

My main worries about the race is the ability "Aspect of Growth" as the healing might be a little too much.

• Ability Score Increase. Your Constitution score increases by 2 and your Wisdom score increases by 1.
• Age. Bo'tirnan mature slowly, being considered young adults by the age of 60. Theoretically, their lifespan is indefinite, but most die before they reach 1000 years of age.
• Size. Young Bo'tirnan are of similar size to humans, though ancient ones can reach the size of ogres or goliaths. Your size is Medium.
• Speed. Your walking speed is 30 feet.
• Sleep of The Ancient Woods. You don't need to sleep, and magic can't put you to sleep. You can finish a long rest in 6 hours if you spend those hours rooted in soil or loose earth. In addition, this rest can replace the need for food and drink.
• Treehome. Your plant-like body is home to many small animals willing to aid you. You know the mage hand cantrip, and when you cast it with this trait, the hand takes the form of a swarm of tiny beasts such as beetles, ants or mice. The cantrip also doesn't require components when you cast it with this trait.
• Aspect of Growth. As an action, you can expend one of your hit dice and regain a number of hit points equal to the result plus your Constitution modifier. You can use this feature a number of times equal to your proficiency bonus and regain the ability to do so when you finish a long rest.
• Kindling. When you are hit with an attack or fail a saving throw against an effect that deals fire damage, you take an additional 1d4 fire damage.
• Languages. You can speak, read and write Common and Sylvan.

Answer 1

It is weak

Firstly all of the features on their own, then summary(you know, beside the summary at the top).

• Sleep of The Ancient Woods - More flavour than anything else, but can be considerably more useful in the campaigns that use the exploration of the wilds as one of the main premises. That being said, it is far from being a strong feature, just because of the very little tables where every ration is counted, and enemies use sleep magic.
• Treehome - Mage hand is a very nice spell, and ability to cast it without components allows some shenanigans(not much) with soundless casting.
• Aspect of Growth - Hmm. You should not worry about this being too much, it is not, never really will be. This is dvarven fortitude feat, just without ASI, weaker(takes your action, not being an addition to the dodge), and more limited(prof. bonus times). And the strength of this feature is strongly dependant on the type of play you and your table goes by. If you fight between long rests, barely using the short rests - this is somewhat decent way of regaining hit points, staying healthy between those few fights, or healing from environmental hazards(not really useful in the fight, you will not outheal enemies wth this to the reliable extent, if outheal at all). If you go by Dungeon's Master guide, and go around two short rests for one long, this is borderline useless. Anything between is, well, between those two spectrums, but it is never a feature I would call strong. Removing the limit on uses would only strenghten the first case, doing nothing to the second one, making this way too polar of a racial feature to have.
• Kindling - This is a no no. The idea of the current 5e balancing is, you should not include features, even those that are flavor or just make sense, if they are punishing the player for playing the option. That includes feats, classes and races. You might say it is a small amount - it is - or that it would not be always at the effect - true. But trust me, or you know what, don't - it is not a matter of trust, but think - every single time you will take this damage, player will be "hmm, sucks I play this". Maybe not by a lot, but every single time it will happen. That being said - if flavour is the key, you can leave it as it is.

This race does not commit any sins of balancing races(safe from Kindling), but it is weak, really weak. Two features are useful only in certain situations, and not really strong, just useful. One feature is good. And one feature is bad. And that's all that is to it, nothing to build upon, to make builds based on, or complement already existing options in the game. Some I guess nice things to have, and a flaw for playing this race incommensurable to the benefits. It is a gimmick race, that does not feel strong, not even mediocre i deresay, and every time you will fail that save for the fire damage, get hit by flaming sword or burning fist, it will feel weak.

What I would suggest? Two options:

• Slightly buff the race, maybe give it one more feature related to plants(plant talk, dunno), and get rid of the flaw. Or
• Make the race worth playing when it have the flaw, give it a mechanical advantage to being a plant people that outweights the drawback.