"that would be one long slow boring trip in a 172"
With almost a PPL and complaining about the possibility of a long trip in C172 being boring suggests you may be aiming for the wrong profession. With your level of experience "Excitement" will inevitably come your way - in aviation you don't have to go looking for it
Crossing the Pacific is a long boring trip if you are lucky. You will learn that boring is beautiful - if you are really bored you have probably overlooked something.