The more mundane, day to day stuff is where there's a big difference.

(Young) Obi-Wan gets super powers and a highly respected position in society that allows him to operate independently on a day to day basis.

O'Brian gets dragged out of bed in the middle of the night because a hypochondriac feels a tingle, and after extensive diagnostics show nothing is wrong, he's ordered to take the transporter apart piece by piece and put it back together again.

During a disaster where he is the most experienced person left on the bridge, he has to take orders from Troi (who needs him to explain everything to her)

Has arachnaphobia, gets stationed somewhere that's overrun by giant spiders, just has to deal with it.

Let's not forget that Miles fought in a war against the Cardassians, which caused some serious psychological scars that don't seem to be getting addressed. Those same events broke his commanding officer, and Miles is the only one who really understands why.

Then he goes on to take a quiet post at a space station in the middle of nowhere, only for it to become the frontline of an even bigger war.