As for comfort and speed humps. As you can see my FD isnt a very functional height lol.
To get a car to sit low like mine (60mm) from the front lip. You would have to upgrade the springs to a more stiffer set.

Honestly, My dampers are set on max and its really not that bad. No ones ever complained about it being to harsh.
Parents are fine, Family dont complain and little cousins love it.
Plus in summer its awesome. Girls with low cut tops sitting at the front in a bumpy car.... Well.. I'll let your imagination do the rest lol

And as of speed humps. I have to crawl over that shit. The ones around my area is fine as I have figured them out and can get over then pretty fast.