I absolutely agree with JMA and will explain my answer, which might sound similar.

First off, reclaim your personal authority and quit giving it to other people.

Have a google of "locus of control" and begin to make your locus of control internal, not external.

Stop the pedastalising.

This can be scary at first, but I assure you that if you take back your own authority, one of the things I have found is that your learning around these subjects will increase ten fold. Instead of being a leaf in the wind, absorbing whatever direction you are blown in based on "well this person said this", you can learn discernment.

I made a pact with myself a while ago. I will share it here with the intent that others may feel called to do the same.

If the information does not resonate with me, I don't care who or where it comes from, or what it is...If my inner being does not agree with it, then it is not true (for me).

I will only absorb something if it resonates with me.

Secondly, learn to tolerate ambiguity. Become friends with being uncertain, being unsure, being in a state of discovery.

To be able to tolerate ambiguity, you must be able to trust yourself and your inner calling. You must learn to "sit" with ambiguity and "sit" with unknowigness

I get the impression you desire a fixed, solid bit of knowing on this subject of thought vs vibration vs emotion. Here is a question I have for you: If you get the answer, how does this change your behaviour?

Eban Pagan famously quotes,

Learning = behaviour change

What state of being will you embody if you get the information you seek?

Will your behaviour change?

If life is about moulding clay or if its about thought and vibration, how will this knowing impact your life?

What is the worst thing that will happen if you don't get an answer to your question?

Despite my challenging tone, I wish you well.

Which one feels more right to you? Which one feels better based on your emotional guidance? There is a spiritual saying, that, at a certain point in your journey, if you meet the Buddha, you have to kill him. This means starting to trust your own perfect knowledge of what is true. Your emotions are always pointing you in the right direction, like that kids game:...colder...warmer...warmer...

One of the best things you can do is follow the doubt you feel. Sometimes that's difficult, because with it may come a sinking feeling that you are losing something you once resonated with so deeply. But you are evolving, and what resonates at one time may not at another. Your emotional guidance trumps everything.

I can't answer your query the way you've asked it, because everyone has different experiences, and all are valid and true, and oddly, sometimes ideas that seem contradictory to each other are actually not. They are just expressed differently, yet point to the same thing. But you're completely unique, and when you investigate your own exquisite authenticity, you may find a third, different option from the two you've listed above, that you never even knew existed...maybe that nobody knew, and if you share it, it will resonate with others.

Doubt about what others say, wheresoever there lies an uneasiness, is a huge asset, if you follow it to its conclusion. It recognizes your own greatness, and it helps you let go of anything that does not align with that greatness.

ETA: I was just making coffee and thinking about a conversation I was having with a friend and I suddenly realized what we were talking about would fit here too, and maybe it will help:

Other people's words can have great value, but your own authenticity is priceless. :)

ETA # 2

I just had another thought of how to explain why the question can't really be answered. Let's say I want directions to your house, so I ask what route you take to get home. Your answer will vary depending on whether you fly a helicopter, or ride a bike, or run, or have mad ninja skills, or are a working uber driver, or never leave your house at all. :)

How to reconcile the ideas "The Universe gives you the essence of what you think" and "Thoughts become things"?

For me they are together already: the Universe gives us the essence of what we think, and it's this essence that comes expressed in things in our life.

Or I'd better say, this essence comes expressed in the feeling you have from experiencing meeting these things.

And then the precision of getting what you built for, depends on how much what you imagined was expressing the essence.

Can you feel it, or you want more details of this point of view? if you like this idea :)

it seems I've never been able to 'shape' something into existence by way of a dominant thought

It probably depends on how you did that 'shaping', and how you saw the results. Can you elaborate on it?

You can play with the shaping in these processes: 38. "Progressive jpeg" (creating from general to details) and 35. What's in it for you. Happy feeling to you! :)

"Many people say you vibrate in a certain frequency, and you are matched with manifestations of the same frequency. But others say thoughts start to take shape and become things".

there is no paradox. when you vibrate in a certain frequency (and your indicators for your frequency is your feelings) then your thoughts automatically changes. the fequncy of fear has its own thoughts, the frequncy of anger has its own thoughs, the frequncy of hope has its own thoughts etc.... and in each frequncy you see/ encounter other things becouse you perceive them in diffrent ways.

so trying to control thought would be alot more difficlt than controlling vibration, because vibration contains thoughts within it. but if youre feeling good already and sure about yourself then controlling thoughts is easy, because you know you want to stay in that vibration.

so we're vibrating in a certain frequency, an than attracting thoghts of the same kind of that frequency , and these thoghts become things.

so if youre focusing on the things alone , you can creat contrast whithin yourself. but knowing that the frequency is the core of everything gives you the opportunity to try and controll your vibration. and while feeling good , think about the thing you want, and why you want it, and what you will do to get it, and how you behave when you have it. and from this window of time of feeling good you can practice a new set of behaviour/thoughts/feeling for 30 days.

Both.

You are not creating alone- you are co-creating your experience with your higher self. If you take both into account, you are doing all your creating alone- truly everything that happens is you setting it up.

If you take mainly yourself as an earth-focused mind into account, well then it is really both. You have an influence, but you have to leave a lot of leeway for how you and your higher self set things up before you were born, and for all the other beings around you who all have their influence.

I find that becoming good at creating is mainly about learning how to chose areas that are both very important to you and that you can reasonably affect.

Hence, the answer is: It's both.

You can lean any way you want- I've been letting the universe (my higher self) fill in more details lately because it's a lot easier and you get more pleasant surprises. But I'm very specific with the lower end of my money goals, for example.

You just use both at whatever they are good at- if you are dealing with something that is already meant to be counted and defined, like money, then you can be more specific. If you are dealing with something that is more intuitive and vague, like relationships or art or culture, I find it works better to let the universe do more.

You can also combine it- I started doing a lot of creative workshop work towards reaching a certain number of people with my art, and I found my art became much more "poppy" or "punchy" without losing its deep qualities at all.