Had a go at using the free Microsoft Keyboard Layout Creator (v1.4) to create a keyboard for learning to touch-type in runes, and one using the Phaistos Disc characters.
After defining the keyboard by mapping the relevant Unicode points to specific keys, then creating the DLLs and associated files automatically, the running Setup to install the keyboard, then selecting the keyboard from the Language Bar, typing on the Runic keyboard produced runes, and Phaistos Disc characters on the other. Amazing!
Definitely better than adding them one at a time via Insert | Symbol, or typing the Unicode hex value and pressing Alt-X.
(Of course, the appropriate font is required, as well: Aegean, Quivira, Code2003, Noto Sans Phaistos, etc. Some fonts are better than others.)
Next step: how to make the keyboard setup files available.
One unintended consequence is, as the fingers brush against the various key combinations, the Runic keyboard (which has been added to the Language Bar) sometimes activates and I find myself ᛆᚷᛝᚢᛘᚼ ᚢᛘ ᛂᛈᛘᚢᚦ ᛐᚢᛆᚠᛛᛈᛆ ᛖᚲᚤᛘᚢᛘᚼ ᛆᛛ᛫ᚤᛘᚧ ᛄᛛᛖᚲᛆᚢᛖᚲᛄ ᚢᛆ ᛆᚤᚭᚲᛄ ᚤ ᛐᚠᚢᚱᚲ ᛆᛛ ᛘᛛᛆᚢᚲᚦ!