Numbering and bullets in Word docs keep disappearing

cdarrow To address the first part of your post; I find that when I set up a paragraph style to have no numbering, and a list style to use that paragraph style, once the list style is applied to an instance of that paragraph style, re-examining the paragraph style in the Modify Style dialog box shows that the paragraph style has inherited the numbering from the list style.

As regards your second point, on document defaults; no, I've not tried experimenting with that, but I can confirm that I, too, experienced the problem with conflict between settings given to table styles, and settings given to the text used inside the table style.  You cannot tell a table style which paragraph styles you'd like it to use for headings, first row, last row, etc.  My workaround for this has been to create a table style, insert a table of some standard size (say, 5x5), assign my paragraph styles within the table as desired, then highlight the whole thing and make it into a quickpart (Insert > Quick Parts > Save Selection to QuickPart Gallery).  If you save this to the "Tables" gallery, your pre-set table should appear as an option in your "Quick Tables" (available from Insert > Table > QuickTables).  Further, if you give it a handy name, like "_5x5TBL", just by typing the name and hitting F3, your saved quickpart will appear. You can include a caption when you create the quickpart too, so it will come in auto-captioned, if you like.

I know that's not quite what you asked; I haven't messed with the defaults because it doesn't sound like that's going to achieve what I want; I want to be able to insert a table where the paragraph styles of the contents match the paragraph styles I intend to use. That's been my best solution so far.