That's my point exactly. In fact, you can't expect a precision better than 10 degrees. Because anything you can get from a typical baseplate compass will have a comparable error introduced by its very design, dictating a certain overly inaccurate measurement technique. The cheap compass, I showed above, is having many of the issues of a typical ancient design resolved quite well. Yes, the parts are cheaply made, but they are doing what they supposed to do at improving the accuracy compared to any fancy plastic baseplate type. But I can easily agree that the 0 mark of its azimuth dial may be off by a bit. Though, I have checked mine for concentricity (mount it on a tripod in the open field, take a fix to one object, go around the compass and see what's exactly in the opposite direction (it has symmetrical sights), now rotate the compass on the tripod to point to that second object, and compare the new fix with the first one, must be 180 deg difference), it's ideal. And that's all what truly matters for a good compass mechanics. I don't mind correcting for the magnetic declination, so if I'll find that my dial is off for some degree, I will just use that delta along with the declination correction. Know your gear before you go anywhere.

Regarding the bubble, sure thing, if it's touching the sides already - the compass is defective and not usable, as the needle ends will be floating. I'm talking about rather small bubble, which is significantly smaller than the needle's length.

For the leveling - have you ever hiked in the steep hills with a compass? Especially liquid filled compasses may have problems there, as you have no natural sense of leveling it standing on a slope, and any equilibrium movements of the needle itself are effectively dampened. Leveling of any compass is very important if you are taking bearings to align with the map or directions list. A dedicated bubble level is nothing special and easiest to use leveling aid on the go.

Tripod mount for the compass is a godsend for triangulation, when you need to measure a distance, locate yourself precisely on the topo map between the benchmarks, or need to create such a map from scratch. Sure thing, for going out of the bush to a road a button compass on your watch band will do just fine.