1. A non-b visa and extension of stay based upon investment applied for at immigration requires a 10 million baht investment. The 10 millions baht can be in a fixed term bank account, government bonds, a condo purchase or all 3 combined.
Your wife could get a non-o visa for being a member of your family and a one year extension.
2. The LTR visa has not been finalized yet.
3. Thai Elite offers a family membership that might be good for you. See: https://www.thailandelite.com/#/