Shear is a problem when the air is dense. Get high enough and go slow enough and the effect may be minimal. Not sure what the Steve Fossett around the world attempts depended on, but the balloons he flew could certainly manage vertical changes as required.
While the visible presence of the Chinese balloon was noteworthy, there doesn't seem much that satellites don't already provide. The one thing a balloon can do is get accurate localized atmospheric composition - water, CO2, CH4, et al. Satellites can do full depth readings but getting details is difficult.