Tell the readers, just not on the cover
The author Seanan McGuire writes some of her books under the pen name 'Mira Grant', and actually includes the line
Mira Grant is a pseudonym for Seanan McGuire
In the 'About the Author' section of her books.
This works for her because she is not using the pen name to conceal her identity, but instead for branding purposes to distinguish between the two genres she writes in.
The first two reasons you give are essentially branding issues as well, and could be solved the same way. I don't know what kind of author information is typically provided for the type of book you are trying to write, but even if no information is provided than you can go with Dale's suggestion of including it in the copyright information, which has a slight bonus of being even less likely to be read.
This is not a solution that works so well for your third concern. I suspect that you are not in as much danger as you fear - there's not much a person can do with just your name and area of technical expertise, and people trying to take advantage that way are more likely to chose targets that they can find significant amounts of information on instead of those like yourself who keep a small footprint. But if it is a concern, than you will have to find another solution.
Embed a personal reference in the text
A reference that is significant to you and your family, but meaningless to everyone else, can be a perfect way to 'prove ownership' of a book to the people you want to convince.
This may be easier or harder to do, depending on the exact nature of the book you are writing. If you're writing a story it's easy - just have the characters stay at the "Spanish Emu Inn", or whatever your family's favorite in-joke is. Technical writing is harder, but if you have any examples that involve arbitrarily named people than instead of using Alice, Bob, and Chris then fill the names with the names of people or pets that your family will recognize.
Some creativity will be required to fit in a hidden reference that is both recognizable to those in the know and unobtrusive to those who aren't. But done properly, it could be just as strong evidence as your name on the cover would be.