That is the broad-stroke version of their differences, but it's a little more complex than that.
The Balance is an old school approach to boots. Both the Oileds and ProTechs use leather that is so expensive, it is almost never used any longer. If you cruise EBay at all, you will occasionally see boots from the 70s for sale, and some are even in good condition. The reason is that the leather used back then was true full grain, without the top surface shaved and stamped like they do now (the tanning was also different, but that process had to be cleaned up). The sole is welt construction, meaning it is stitched. 5 years down the road, if the sole is worn out, it can be replaced. It also is more rigid.
The Adventures use leather that is thinner (2.5mm instead of 3.5mm) and softer. The whole boot is lighter, softer, more comfortable, more easy to walk in. It is a modern design. Quality is excellent, they are great boots, durability seems solid (they are new, so this has to bear itself out) but....they are a modern design. I am a bit of an old school guy for products, especially boots*. Old school footwear, especially boots from the Veneto region, had a well earned rep for lasting (ha ha) a long, long time. They could be repaired, resoled, and handed down to the next user. The Italians from that area have a ridiculous obsession with quality, and complete disdain for modern approaches to building footwear. I lived there, and knew several of the product guys. For them, it has to be simple, use the absolute best materials, and they spend absurd amounts of time refining the details until the product is late, over budget, unprofitable, hard to manufacture......and excellent. The Italian companies are still competitive with Asian-made footwear, but at the expense of their obsession with quality. The Balance is one of those old-school products. The G-ADV is a modern one.
People who buy the Balance have almost universal praise for them. They are not a good ADV product, they are one of the best ones sold, period. I am not being hyperbolic or disingenuous, I really feel that is true.
*looking for a pair of vintage red-lace Dunhams in size 12.