Next time I teach a version of this lesson, I may not ask students to find the unit rate at all. Instead, we will work on modeling decimal increments such as 1.5 or 2.5 to help build their number sense. I often saw errors on double number lines such as 0 followed by 1.5 then 2, 3.5, 4 or some such variation. A number line with tenths, for example, may have been more helpful for my students.
I allowed students to use calculators to make working with the numbers easier. Since this is the first time during the school year that I have allowed my students to use calculators, I should have built in more time for them to find multiples of decimals. Unfortunately, my calculators do not do repeated operations as easily as most calculators where you can press something like 0 + 1.5 and continuously press the equals button to see the next multiple of 1.5.