Funny, cos I did long haul in the first part of my career and began to hate the boring flying and layovers, and was much happier getting home every night, with about one to two 4 sector days every week ... and far greater job security. That said, I think the optimum is to start off with about 10 years of short haul to hone your skills, then try long haul before getting too old. Or join a flag carrier (the advice I wish I had taken at age 25) -
In fact, the best advice i ever ignored is, 'the worst thing to happen to me would be taking that very early command - so I did indeed end up hopping from one shakey start up to another, determined to keep the left seat. My advice - read 'Fate is the hunter).