In my opinion:
1. The FP+ lines are longer because a. you have gone from a system where a CM takes a quick glance at a piece of paper as people continue walking and usually only looks briefly at one of the paper FPs for a family instead of scrutinizing everyone's FP (or where in our instance, I would hold all 3 FPs in kind of a fan shape for my family and the CM would take a quick glance as we were moving through), to a System where each and every person must completely stop, put their arm up to a sensor, make sure they are lined up properly, and watch the sensor spin until it turns green. If this adds 5 seconds per person, which in my experience I would say it does, then this means a minute wait is added for every 12 people that go through the line. If it adds 10 seconds per person, then for every 6 people that go through the line another minute wait is added and b. its is my understanding that they are issuing far more FP+ per day than the FP- they allowed to be issued per day which means more people in the FP+ line.
2. The standby lines are longer because a. most of non FP queues were not initially set up for 2 lines, which creates more of a bottle neck when you are trying to funnel 2 lines through and the stopping; b. again on the old FP rides they are issuing far more FP+ per day then they were issuing FP- which puts more people in the FP+ line and as for standby they also issue more FP+ than the would have on a FP- ride which puts more people in the FP+ line, which means that the standby line gets stopped more often to let FP+ people in, which backs up the standby line.