With low seniority you very seldom get to south America and USA, Australia and New Zeeland, but end up in Africa some, but mainly Asia.
I've a very low seniority but I do go to all the above mentioned parts of the world except South America.
If you're over 40, forget about it - unless you're SURE that 3 stripes will make you happy until you retire.
You think it might take >20 years for an upgrade?
I think that anything between 10 and 20 years is realistic.
Oh well, still better then flying short-haul with 4 stripes.
Overall I am very happy to work for Cargolux
Good luck!
E Le B