Don't be scared OP! We've done three trips now with the new system and I quite like it. I think you could also classify me as a 'FP Super User' or 'Recovering Park Commando', the people most complaining, and we still really liked it. We found ourselves sleeping in a few days instead of getting up for rope drop every day which was nice for a change. Despite how it appears on the surface, the system is actually pretty flexible. Each day of my trip I rearranged times for my FP+ selections. It was easy, there were never any availability issues and this was including days with 10 level crowds. There were often times that instead of waiting 30 minutes for my FP+ window to come around I would just reschedule the ride to be right now, and walk right on. So awesome!
The bands are handy too. We still did rope drop many mornings, and we found that we never really needed our morning FP+ reservations so I wound up rescheduling them for afternoons. I also went armed with 15 past room keys (shame on me I know), to pull legacy FP, and I never really used them, so I know it will be okay when the paper FP goes away completely.
Book a trip. It will be different. But embrace the difference and you will have a good trip.