What is it you would like to do relative to what you, pragmatically, can do? Financially, personally, or otherwise.
I would like to rent an apartment somewhere in Europe for a month or so, but my wife is more of a homebody and after 7-10 days is ready to go home. Thus, we compromise and our trips are 7-10 days :-)
Part of me would like to travel to Russia and Australia, but the length of the flights is a deterrent. 8 hours, give or take, is about my limit. Maybe I'd be willing to consider it if I could afford first or business class.