Of course friends.…yes it is uncontrolled growth right now to beef it up and plan which branches I’m keeping.
Let me try to repeat the advice already given in this thread, but state it in a slightly different way.
With bonsai, you never want uncontrolled growth. Even if you are growing a sacrifice branch, you should always have a plan. Even trees that are planted in the ground to gain girth quickly will have a plan. They will have a trunk line that is being developed, secondary branches that are temporary, sacrifice growth that is going to be removed, etc. Growing a mop of a tree and "topping it" is not a plan... it is the lack of a plan. I don't want to come off sounding too critical - but it is not going to get you where you want to go.
When planning your tree, start with an end vision in mind... and then guide the growth of the tree to fit that vision. Since your tree is in early development, once you establish a vision and use wire to shape the lines of the trunk, everything else is secondary. Short of killing your tree, you should remove EVERYTHING that isn't part of your final plan. In some cases you will leave A SINGLE branch as sacrifice growth, or you will have to leave keep some bits of foliage so the tree doesn't die, but those are temporary and not part of the final tree. Anyone versed in bonsai should be able to look at your tree, even in early development, and say "oh I see where you're going with this".
Right now you are uncertain, and so you are holding off from diving in and aggressively pruning the tree. Rather than keeping options open, you are actually just delaying the inevitable, and lengthening the time that will be required for wounds to heal, for the tree to adjust its strength to the new plan, etc. Because wiring and bending a tree stresses it, you may find the tree simply grows AWAY from your design - and your selected trunk dies while all the growth you left undisturbed gets stronger. You will be left with the negative image of the tree you were hoping to create.
FWIW with a tree this size, you should assume that you won't be keeping ANY branches - because they are all too thick relative to the trunk. If you looked at your tree and asked yourself - stripped just to a single trunk line what would it look like? That is your tree. Eliminate everything else while letting the single trunk be the only part of the tree that isn't cut back and let it grow strong. A tree this young will sprout new buds all up and down the trunk, and those will become your second generation of branches that you can better work on to balance with the strength of the rest of your tree. But the tree will already know "oh I know where my trunk is now" so you won't struggle as much with undisciplined bush-like growth.
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