Coffee Ice [or...Granita?]

I'm technically not supposed to have much caffeinated stuff anymore due to the fact that it apparently interferes with methimazole efficacy, but this was made with decaf coffee [so, it has 2% of the caffeine it otherwise would have] which means that it probably has the same caffeine power [if not less] as some chocolate. I started off with coffee, fat free milk, some honey, and some saccharin. I froze it for an hour, and it looked like the image above.

An hour later, a layer of ice had formed on the inside sides of the plastic container, but the centre was still liquidy [or, slushy, after I mixed it]. The whole point of making this is to chop up the ice crystals every hour or so. I actually should've used a shallow container, since it was more difficult to reach the bottom parts which were frozen.

In total, six hours later, this is what I ended up with. Granules of frozen coffee and milk! The volume had [evidently, due to not only the lattice structure of ice, but also to the air between each crystal] increased to... about 157% its original liquidy volume.

I'm not sure whether this is "Italian Ice", "ice" or "granita". When I was younger, my brother and I used to make watermelon granita, which I recall included 150g of caster sugar dissolved in water, a lot of watermelon juice, and lemon juice. It was made in the same way as this, and did NOT taste like artificial watermelon flavour. It used to be such a big deal! Today, I felt like making this since it's too humid to drink hot coffee [even though it was pouring with rain all afternoon] and I felt like this would be yummy. Before freezing, the slurry tasted like normal sweet coffee with way too much milk [I tend to like coffee without milk]. After freezing, I feel as though it tastes even more watery than originally... which means that next time, I have to brew super-strong coffee. This is saying something, since I generally make really strong coffee. However, it isn't super sweet, which is great. I'm just worried that it's going to freeze into one huge mass by tomorrow morning, since I probably didn't add enough sweeteners to keep the ice not-that-frozen, since adding sweeteners means that the freezing point of the solution increases, which means that, in theory, the granita would freeze at a higher temperature [because the sweetener molecules prevent the water molecules from bonding to each other as efficiently].