I tried this mod out, and overall really liked it. However, I found that in most cases it would make every item used take an extra slot. This is because either a) you accidentally place and remove an extra item, or b) the item is crafted in units of two.

Personally I solved this by having it craft when less than 80% full, rather than 100%. It works nicely, and suggest considering either adjusting it by default (maybe 90%?), or putting in an option for this.

Try out 1.1.0 :)

Didn't read your post before I released it (No notifications at this forum, that's why I recommend the homepage/thread at the factorio forums). So for now 0.5 stacks is the smaller-than-one stack size limit available. Try it and tell me what you think. I will consider another setting between 0 and 1 at about 0.8-0.9 stacks once I have figured out how to do migrations correctly ;)

I had to double-check the timestamps, because I actually noticed the update, and read the changelog on my way to re-do that change. I like it, although something larger and smaller within a single stack would be nice. I noticed myself wanting to use it, for (for example) assembly machines in early game, when affording 25 of them is still an excessive proposition. Perhaps like 5 or 10 (or both, if it's easy). 0/5/10/25/45. I'm going to repost this on the forums to continue that discussion there though, as you said it's better.