Blob Brush Keeps Changing Settings

It is a bug that adds to the clunkiness of Illustrator. No other software I've ever used comes even close to how much fragmented and all-over-the-place Illustrator is. It can be a lot more simpler and smarter and way more streamlined, but well...
The Blob Brush stroke size apparently uses the previous setting to do some math and determine the new size. If the initial number is 1, which is the default when you switch tools, any other size you input will return "1" as a result, due a faulty equation apparently. It works fine with the regular brush tool, and since they somehow use the same library, when you switch back to the Blob brush, the stroke size will work as expected, until you switch to another tool.
This is a stupid workaround, but there are 2 other alternatives:

- double-click the Blob Brush icon in the tools palette and choose the size that you want (this size is read before the stroke size and still works)
- Use shortcuts to change that size. By default they are "[" and "]" (many shortcuts from adobe are only compatible with QWERTY keyboards and even if they try to adapt, they still don't work with other keyboards). To change the hotkeys, press "Ctrl+Alt+Shift+K" and look for "Diameter" in the "Tools" category.

I'm using CC 2021.  THIS IS A BUG!!!  When I use the blob brush at 75% opacity and I color a portion of the artwork, then color a non-adjacent detail using the SAME COLOR AND OPACITY, when I attempt to add to the original area using the ORIGINAL COLOR AND OPACITY, Ai automatically converts the opacity of the new area to 100% opacity and treats it like a separate object.  I have tried setting the opacity before using the BB, it reverts to 100% opacity.  I tried setting both the stroke and fill to the desired color at 75% opacity, Ai converts any new BB applications to 100% opacity.  If I go in and select the newly applied area, then change the opacity to 75%, Ai will change the opacity of the new selection to 75% BUT, instead of an undetectable join, there is a darker area where the two applications overlap.  When I delete the non-adjacent details, further applications using the BB works as expected - the new area is added to the existing area at 75% opacity and without an overlap.

The Blob Brush always draws with the stroke color. If no stroke color is assigned, it will shift the fill color to the stroke. If a fill and stroke color are assigned, the fill color will be eliminated. When you deselect the Blob Brush, the area that was covered with the brush stroke becomes a unified fill. If you want a stroke around the generated shape, you can add it at this point; you cannot apply it as you draw with the Blob Brush.

To adjust the size of the brush, use the left and right square brackets, [ to make the brush smaller or ] to make it bigger. The displayed stroke size will always be 1 pt.—do not use stroke size to set the brush. You can also double-click on the Blob Brush Tool in the Tools panel to set the size and other aspects of the tool.

Peter