The gpa thing is not true. I got invited to a R1 school and I have a 3.25
I did 1 postbacc/gap year and it was great. I got a chance to get more awards that boosted my applications. Try not to see gap years as failures, please. They're quite fun. GPA is not the be all end all, many neuro programs look at you as a person and not just a set of numbers, which is why many schools dropped the GRE.
Also, people coming directly from undergrad are at a disadvantage since they don't have much full time (emphasis on full time) experience. Many, if not all, programs want a year MINIMUM