75 to 85 WITHOUT ATLANTA...

LOL dozens. Depends on what's going on with the main route, time of day, and how wide a berth you want to give it. GA-141 up to Jimmy Carter then back to I-85. Or Winters Ferry/Amwiler and Jones Mill over to Buford Hwy cut thru Best Friend Rd area. That whole area is industrial. Just avoid the old town Norcross. The whole old town area is truck restricted. Most of the streets in old Norcross have steep r/r grades you'll bottom out on somewhere. Keep to the 4 lanes and you won't have trouble. You can even catch GA-400 NB to GA-369 and across Browns Bridge thru Gainesville.

All in all it just depends on if the alternate isn't putting you into worse traffic than you're already in. Another good one for when the 85 NB ramp you would normally take is jacked up, but coming the other way is better. EB on I-285, stay all the way to the right and take the I-85 SB exit. There is another ramp for I-85NB off that ramp that will merge you in right on the flyover. Or, ease back in the left lane on the ramp and get back on I-285. Exit at Northlake parkway (posted no return access, but you don't need it), make a u-turn on the overpass, and hit the I-85 NB ramp going the other way.