Proper flying??
No such thing, or it's all proper. I fly a big shiny fast lump of aluminium with lots of people, knobs, buttons and switches on board to earn money. I spend hours trucking across continents, seas and oceans monitoring, checking and programming bits of ultra-clever, hi-tech stuff. I love it too.
However, on a day off I like to keep my SEP rating valid. As an ATPL holder I am allowed PPL privaliges, provided I meet the same currency requirements as a (brown licence) PPL holder. Also, because I have a UK ATPL (rather than a JAR one) I am also allowed to excercise the privaliges of an IMC rating. Not sure I'd want to though.
I couldn't rate one against the other. I love flying from one big international airport to another 1000s of miles away in a highly rated Boeing. I also love pottering about Berkshire at 1000' occasionally venturing into Oxfordshire in a highly rated Piper Cub. Marvelous!!!