I remember one of the times I went to a seminar working with what we called "lightbody". One of the very early meditations we did was suppose to clear out symbols. Stuff we read and we choose to carry. By then I had filled my understanding with Trees, pillars, rays, polarities and all sorts of other stuff. Was very interesting to feel and see how all that is washed away and the freedom one senses after that happens.

Of course, back then something like that can't be kept for long, so the years after I read more stuff, recreated many of those same symbols, although leaning on new ones and one day in another seminar we did similar meditation and all of it washed away again.

By then I had the concept a little from other places, we aren't suppose to "imagine" stuff happening, we were suppose to use part of this mechanisms to interact with what is already there...

But took me a while to understand why. And of course, part of it may be obvious, if we paint on top of a painting instead of understanding what was there we will make a mess. Then one has to figure out what they destroyed and what opportunities that carried, but at that point will be difficult to accomplish.

So there is a "shared" reality and from some points of view we are here to learn how that works. Imagining how it works on top of it, is not a very productive idea. That whole journey has been covered in great length in "never ending story"(the book), while I'm not sure I can recommend its English translation, the way "creating" with Imagination works is perfectly described in it as far as I'm aware and it leads it to the other way of creating at the end.

Anyway, back on "why". Why not use imagination, we can imagine we are awesome and great, for confidence, we can imagine we can do something we can't to feel less restricted by limitations etc.
Well, first because there are reasons there are limitations and if we lack confidence there is reason for that as well. Imagining other situations may lead to great lessons, that are unlikely to be for us, as that aren't our situations or lessons to begin with.

As again, there is a vast "shared" reality we all are part of. Knowing it is worth it. Imagining its different is not.

Hipnosis and trance states are interesting to study. Milton Erickson and others... We can see the interesting idea, if we ask someone in trance, about the great green flying saucer that they were in last week and we do it in the right way, they will go in great lengths describing the event even if it has never happened.
Some can call that "false" or "phantom" memories. Memories can be created.
One of the problem with past lives. If we look purely in the trance phenomenon we can't know if the person had "past" lifes or is just creating stuff because is asked in the wrong way.
Of course, that is easier to deal with as we have people that remember that from very early on, some never forget, so we can see it in other places and know its somewhat valid.

But the idea is, our mind has tendency to create stuff if something isn't there but it searched for it. That is studied a lot. Imagination carry the same problem. As the "created" stuff, doesn't become real, or to be more correct it never "aligns" with the reality behind it.

So is Imagination bad then... And no, nothing wrong with it, there are steps one may need to take with it before it becomes useful(again very nicely described in Neverending story), but eventually can be useful.Here someone may wonder - why recommending the Blue Schools and aren't they working with Imagination... And no, they are not. But need time to figure it out, they use other mechanisms that are very important, but not the point, right now.

But metaphysics... We aren't suppose to use Imagination in metaphysics, as far as I'm aware.As again, there is a great shared reality behind it all and aligning different "levels" of it is what we are suppose to be doing.
The more levels we align the more powerful little changes can be.
That is the actual ritualistic work, as far as I'm aware. It doesn't happen by wanting some movement or item to mean something. Its by understanding how it all aligns and then creating very small change somewhere that resonates with many of the overlapping level of wholeness all and everywhere around us. Then something small like moving a rock can change much.

Without it there is tension, pressure and resistance from the system. We imagine we are free, but there is a reason we are not. Instead of understanding that so it desolves leaving us knowing more and much freer then we could be, we carry the problem, the misunderstanding on top of it. then on top of that the decision to overwrite it with something else and on top of it the idea we are free.

That is very difficult to get out of. Well, technically its very easy, but to make the decision to do it requires one to be aware of all that layers. And not everyone can do that, easily.

Summary... I avoid using Imagination in metaphysics work.

Here one may say - but big parts of western metaphysics work with Imagination. There isn't real things behind that they are using they "create" it.
And that is... Well, it isn't really true. There are real structural stuffs for each of the parts they "imagine" as they couldn't see in them. For example the Middle Pillar while there but not fully "made" the whole time, in all its glory shows up after 3rd initiation. That is when the 3 Dan Diens are created by merging the polarity points around them. That happens by itself.
Visualizing light there will not make that faster. Initiations are taken based on structural understanding and knowledge/learning one attains, not because they visualized something that may be contained in their structure after the initiation is taken.

Imagining light there may bring up 3rd initiations lessons, but that also is stuff one is not ready to take without the initiation itself, as their system is not functioining on that level yet. So will only confuse the system. More on that already covered above.

What to do if the system we practice is imagining all sorts of structural stuff that aren't there... Dunno, don't practice that part of it?Or clear it out after, its enough one to want that to wash away and it will, although not recreating it right away is up to them.