The main reason to move is if you want to come across lots of different people.

If you are moving because you think you'll be able to magically do Apex groups, VH Ambuscade and Escha NMs when you could not do it on your old server, that's not gonna work.

The big server is the same as the small server but on a larger scale, most people still won't take you if you don't have good gear or the proper job and the people with bad gear don't make groups.

As long as you come with the correct mindset it's great, if you think moving will solve all your problems form your old server. It wont work out that way.