Hi Susan, and welcome to semp addiction!
You're in good company here!
Sounds like a couple of pretty big projects, but should be beautiful when you're done. As far as amending the soil, if you use sand it needs to be a larger grit so it doesn't compact. The sand/gravel sounds like a good mix. You don't want the gravel too large either. Any idea what size it is? Pea gravel works great. Is the path area planting going to be next to the path, or between the pavers where it will be stepped on?
Be sure to take progress pictures and good luck!
