Recommendation 1: Focus on culture first, technology last
If your kids don't touch a chromebook for weeks, that is totally fine. They need to get used to how to move between stations, work at an independent station, ask for help, turn in and take out chromebooks, walk with chromebooks, open and close chromebooks, etc. before they are ready to actually use them. Technology will strengthen a good culture, but only worsen a negative culture.
Recommendation 2: Keep it simple
Your teachers need to get familiar with blended learning and how it is going to shift their teaching before they will feel comfortable with rolling out multiple stations. I would plan on keeping the two-station rotation simple, and only asking teachers to use ONE (maybe two) programs in the classes. Your innovators and early-adopters may be able to handle more, but make sure no one feels overwhelmed. Tech WILL stop working at times, so we want to have as much success with one program before we expand.
Recommendation 3: Leverage the veterans
You likely will have some folks who are experienced in teaching in a station rotation model, or at least in a blended learning environment. Lean on them. Empower them to lead the change in the building, and ask them for help with they think will work best knowing your kids, your school, and your situation.