Advice - Not the Colors, But the Size
 

I drew this up in my EQ5. I am thinking that the spools are just a bit wide. I am wanting them to be closer to realistic. I know I can easily make them as skinny as I want. What do you think?

I agree, the thread part looks a smidge too wide. Love the stripes to simulate threads. For some reason I want to see white spools. Isn't it funny how conditioned I am to what I sew with. Your's looks like wood which is traditional. Good Job.

I agree the spools are a bit too wide. I love the design though.

if you had not called them spools, i think i wouldn't have noticed that's what they are. i would try to make them narrower, but now they wouldn't be squares... or would you just have more space beside them?

I also think the spools are too wide. In fact I did not perceive them as spools at all until I read your message. I do like how you filled the spools with two different fabrics very close in value and color.

Like the others, I didn't see them as spools, at first glance.
Though with the explanation, they do come to mind as the old wooden spools.
Plus, thinking back, way back .... , there was a wooden spool that more chunky, and would be more like those proportions.

Something to think about ... there are so many different types of spools today, that I so seldom see this older style, even if re-proportioned. Maybe you would want to emulate Aurifil spools? There is a free pattern to make those, somewhere on the web.

I agree, the two close-coloured-tonals works well to emulate the thread.
Good Luck! ... and have fun with it.

I found a different drawing I'd done a couple of years ago. This looks more like a spool, however it's not square and forces me to face them all the same way.

I agree that the thread needs to be narrower. I really like the second picture.

The second one looks like spools to me.

No reason why you couldn't turn the alternates on their sides .... just provide more background top/bottom for the horizontals and left/right for the verticals to fill the space.