What's the best way to manage tons of fields?

I am currently attempting to use layers as an alternative to using tons of form fields, but I'm likely using them incorrectly. Our client wants a PDF with lots of rollover images. We normally create technical drawings with SolidWorks, but tackled this anyhow. My solution was to create hidden text fields and icon buttons. When another hidden button experienced a mouse entry and exit, the appropriate text or image would be displayed. This seemed the proper approach. However, when I started adding more and more images and text fields, they began to overlap, making the document very difficult to work with.

In a test attempt to work around this, I instead created a separate PDF with one of the rollover images statically displayed. I imported this into the "main" or "base" PDF as a layer. Now my hidden button will display a new layer upon rollover, revealing the image as well as the rest of background. So when the layer is shown upon mouse rollover, an entire PDF is displayed on top of the "base" one. This causes what I'd call a "flicker" effect as well as a tick of load time. If I carried on down this road, not only would my file become huge, but I think it would end up being just as difficult to work with, if not more so.

So my question is this: how do I achieve my goal here? Form fields are easier to deal with, but when I attempt to manage an obscene amount within the form editor, there are so many displayed that I cannot see to work. Layers may work, but they're difficult to use this way, what seems impossible to edit, and hard to manage. Maybe script can solve this? I have no experience with code of any sort. Maybe InDesign is the way to go? Some other program? I'm at a loss here.