
That's certainly true. There's a lot of things people can choose to be, and even those adventurers who have advanced far enough could easily have chosen something different.
Mizuki hadn't really been certain how she wanted to advance her own skills, other than that she had to admit that it felt very comfortable to use her own body rather than relying on weapons, and that combining her own life with that of the world around her had a certain feeling to it as well. Her becoming a druid capable of changing her shape had as much been a case of it being necessary at the time as anything else, as she'd changed into a wolf when she really needed some additional speed and some sharp fangs.
As @Madison Freebird mentioned how she considered those who took other paths to be cheating themselves Mizuki tilted her head, then nodded in agreement.

I wouldn't tell others what to specialize in unless they asked for my advice, but the Emerald Garden is certainly worth becoming a druid for.
Seeing that her companion was taking in the sights of the world around them once more Mizuki did the same, with one paw wiping out the stuff she'd been drawing in the dirt before her while explaining as she sniffed the air, swivelled her ears to catch the sounds, and took in the different colours of the world. She still had all the colours in her vision as a wolf that she possessed as a humanoid, but it still seemed like the wolf form helped push the importance of vision to the background and prioritize sound and smell. She could smell the rich earth, the plants around them, the odour that was the signature of Madison's body. She could hear the wind as it moved through the branches, the breathing of the two people in the little clearing. She could even if she focused hear Madison's heartbeat, steady and calm.
It was a surreal experience, and a small part of her wondered how it worked even as the rest of her relaxed, the wolf's posture lowering a bit as she closed her eyes and placed her head against the ground, taking this short moment to completely unwind.
Only to get caught off guard when Madison began to talk again. Opening her eyes she looked at the woman before closing them again, her ears twitching and pointing towards the woman to show that the wolf was listening even as she rested. Once Madison had finished talking Mizuki stretched, yawning and showing a full mouth of teeth before pushing herself back up into a sitting position.

Given that we can ward those thorns away with a mere touch I'm not sure I'd call that dangerous. Dangerous for non-druids, yes, but I think the true danger lies deeper in the Garden, where there's creatures and plants with more than just a physical form. Magic, intelligence, things that could counteract or subvert our druidic powers. A guide would have been helpful, but I doubt the other awakened masteries come with one.
While the Awakened form of nature magic seemed to take a more mystical approach than some masteries (from what she'd heard with most awakened masteries were just the player realizing they could stretch what they already knew further) she didn't think it was quite so special as to guarantee a guide, although she couldn't disagree with Maddy that it would have been nice.
She was lifted out of her thoughts by more questions, these about her appearance as a wolf. Mizuki shook her head and quickly answered the questions, hoping to dispel any strange notions before they became too solid.

This is my beast form yes, but there's no such thing as a single form you have to choose. This form is what I'm comfortable with so it's what I use most of the time. As for how I obtained it and how to teach you, well...
Given that Maddy was a druid who'd already reached the Emerald Garden there was no reason not to help her figure this out as well, although the question was how good of a teacher Mizuki would be.

I must admit that when I figured out how to do this it was in the heat of the moment, so I don't have anything like a complete guide. But if I had to explain...
Mizuki turned back into her humanoid form, fur receding so most of her body was no longer covered while her form lengthened and changed shape. One of the side effects of Mizuki treating this dream world as a place to be free was that she hadn't bothered with clothes, so Madison got a full view. Mizuki herself didn't really seem to care or notice, as she was thinking about how to best explain.

So, when you use your magic on the plants you can feel that they're more than just objects, right? They're alive, they're beings that you're shaping and growing even if they can't speak or think like we do. Using your magic you connect with nature. And this is like... reaching out both further and less so. Since you're shaping your own body you need to have very good understanding of your body, so you need to use your energy on yourself first so you gain that same understanding as you gain of the plants you use. I mostly use my magic to enhance myself, boosting my strength or my speed, so for me that was fairly easy.
She held up a furred hand, sending some of her energy into the limb and letting it completely suffuse her arm before pulling it back in again.

And then you... need to gain the same understanding of the animal you're trying to turn into. I've yet to try turning into something I hadn't encountered before. You need to make that understanding yours, perfectly recreate the essence of that animal inside of yourself. You could call it the spirit of the animal, the core essence. So to turn into a wolf you need to both understand what you are and what a wolf is. And then when you've got both you need to make them match, shape your own body like you've shaped the plants to make your body and essence match that of the animal. But a lot more intense, a lot... more? Thoroughly?
She scratched the back of her head, looking a bit embarrassed.

Sorry, as I said I did it on the fly without really thinking about it, and even now it's less a complicated techique and more me knowing what shape I need to be and how to make my body change into it. So for me it's more like...
Closing her eyes she focused, feeling the energy that filled her entire body, the shape of her body and all its workings. She didn't need to send more energy into any body part, as her life force was in every cell and this didn't require an extra surge like a buff did. She just needed to shape what was already there. Feeling the predatory instinct of the wolf in her core she let that instinct into her mind and body at the same time, body and soul both responding without hesitation.
From the outside Madison would first see something appear around Mizuki, an ethereal shape which quickly became detailed: as if from out of Mizuki the actual spirit of a wolf appeared, large and fierce. And then she got to see the same transformation as before, only in reverse: thick fur began to grow out of every part of Mizuki's exposed skin even as she became shorter, her mouth becoming more prominent as it slowly turned into a muzzle together with her nose. Placing her hands on the ground her fingers became shorter and fatter, turning into the toes of a paw while her chest flattened even as fur covered it. In the end Mizuki was back in her wolf form, opening her eyes even as the wolf spirit became one with her new body.

The best I can say that you need to become one with that which you're trying to become, and for that to work you need to understand both yourself and the creature you're aiming for. It won't work if you're just trying to wear the form like clothes, you need to try to actually become something different, I think... You don't stop being you, you don't lose yourself, but you do change what you are. You can't just treat it as some outer shell you put on and cast off without it affecting you.