The best bar is the one that's attached to a Dolmar 7900! You'll be happy with whatever damn bar you want! ZING!!!!
In all seriousness (which I never truly am) a 70-80cc with a 24" is the sweet spot for me. I don't subscribe to the idea of using a smaller "limbing" size saw much. And before you even say it, yes, I have a job that requires me to carry a saw through the woods all effin day.
At home every time I think "oh what the hell I'll run one of the smaller saws today" I always end up just wishing I had the 7900, 8401 or 372 which all carry 24". (I do love that wrap 6100 though). Mostly the 7900 and 8401. Mostly the 7900. God I love that saw. ......... I digress
I find limbing much easier with a saw with reach than I do with a saw that weighs a pound or so less. By the end of the day the reach is much more noticeable to how sore I am than the couple of pounds.
24" is the cut off for me. 28" feels off to me and I'm basically never cutting anything that requires it. I do run all lightweight Sugi or Tsumura bars FWIW. I carry my saw over my shoulder and the added length to the bar also gives you better leverage with again 24" seeming to be the perfect size.
I bore cut and backstrap every tree I can. If the dbh allows it I'm bore cutting it. Just love the certainty it gives me in setting my holding wood perfectly. I guess unless it's pretty straightforward going with the lean sorta stuff. If I gotta get crazy against the lean I'll triple bore through the face and set three wedges in back then bore to set the holding wood. No shots at anyone here just describing my preference.
Covered a lot of subjects here and some of the tone of this thread leaves me feeling like I need to call someone a dumby to fit in so I'll succumb to peer pressure. THE FRONT OFFICE OF THE CHICAGO BEARS COULDN"T FIND THEIR ASS WITH BOTH HANDS AND A MAP!!! How's that?