It's really easy to leveling after you get your first class on 60.

for each level up after 50 you need about ~4-5 dungeons. Fates, Hunting Logs etc. not included. Let's take 2.5h per Level --> 25h for Level 60.
It's not that much though.

And leveling is fun

But if you are lazy... maybe you shouldn't play all classes. cause lazy players are doing most times no damage in dungeons and are incredible bad ^^