I’ve never thought of using CD towers for storing pedals until I saw this.

I’ve got 15 IKEA white & black ones unopened still stacked in boxes that I can use

It's funny that you mention that!
Currently, 17 Ikea Benno towers, that I purchased, used, on Craigslist, for next to nothing, are taking up way too much wall space in our living room, filled with Blu Rays, DVD's and some CDs (The rest of the CDs are in my bedroom closet). I've been collecting these for over thirty years.
I don't use the towers for pedal storage, currently.
I had a plan of transferring all the DVD content to a brick, so I could have them all in one compact digital storage space, and be able to do away with all DVDs, but it never happened. Nice rack drawers are kind of expensive, but I think they would be a better solution for pedals I want to access quickly, while taking up no more space than is already used up by the racks, which are also in my room. I don't plan on getting rid of any of that rack equipment or the rackmount boxes. Maybe for nostalgic reasons, I hang onto them, and some of them can now have a new purpose.
None of those Ikea towers really fit in my current room (which is my studio, home office (of sorts), and sleeping quarters. Instead, any pedals I have that aren't currently mounted on pedalboards, reside in three under-bed boxes (under my bed, or course).
What I'd
love to do is utilize some of that unused rack space. I don't think I'll ever be traveling/playing with rack equipment, outside of home any more, and if I do go out to play somewhere, it's all going to be with pedals. Easier on my back LOL.
Among the rack boxes, I have an 8-space Road Ready shock mount case, on casters, and a Grundorf 6-space amp depth case, giving me 14 spaces to work with. I picked many of them up, through eBay or Craigslist, with local pickup, years ago, also at an amazingly low price. The other boxes have stuff mounted in them, but these two are free.
I could invest in seven 2-space rack drawers and store all pedals that aren't mounted on boards (but get rotated on and off of boards, as needed), in those drawers - and still have room for more pedals, without taking up any more space on the floor :-).
I know - pedals are my addiction, but one I can live with.
Then, I could move all (or most) of the pedalboards (5) under my bed, rather than having them strewn all over the floor.
This way, I could get to everything more easily, while not taking up so much space on the floor, with those boards. I only ever use maybe two boards at a time (one for keys, one for guitars).
Or, I could just sell a bunch of pedals.
..............yeah...no, that's not gonna happen.
I've already sold off stuff in the past, only to end up regretting it a year (or five) later.