hon...i seriously could have written your post.....coz its almost exactly my situation here...
My H is 7 months....b/fed, wakes 3 hourly....im okay with it now...around the 4mth mark i went thru something (dunno what you would call it ) but was finding it really hard, and really frustrating that my lil man wasnt sleeping through. Got over that....and just prod along now.
Like your son, hes a happy, content lil boy. H will have a sleep 1.5 hrs after waking up (usually 7am), then have a afternoon nap that is usually 2 hrs (first sleep is anything from 45 mins to 1 hr max)...so very similar to your DS....
I have family and friends saying i should go to sleep school, he should be sleeping thru by now, blah, blah, blah...well you know what...he's not, and im ok with that, my DH is ok with that, and my other children arent bothered by it. So who else should care....really ?????

For what its worth...your lil boy sounds divine, and sounds like he is doing just fine...just like you and DH......so enjoy him, coz this first year zips past so fast......and hon...one day, one day he will sleep through.....he's just not doing what the text book says....

GL....