You are asking some deep technical questions based on very little technical information. 6'10" is a livable ceiling height if it allows by passing lifting house. 6'2" not so much. If the floor is dirt,digging is better than raising "BUT" you need to know how deep footing is and how it's constructed and plan accordingly. You certainly don't want to dig past bottom of footing unless you add to it.

Sounds like a really big project.

I wouldn’t expect digging down to be feasible - you might as well build a new house instead. Lifting the house up off the basement could be done, I would think. But pricey.

We live in an area with many Mennonite persons - there are several here who do house lifting as well as house moving. I have no idea if you have such skilled labor in your area, though.

Here’s a picture from several years ago of an older house being moved down the main street in our small town. Crowds turned out to watch.

I would finish it off like it is, unless, you are both so tall, that you will be bumping your head every time, you are down there. Lifting up would be best option, but, it can be very expensive. Digging down, you chance disturbing the foundation of the house.

Thank you for your responses. My husband is 6 feet and I am 5’3. My oldest son is 6’3” and my youngest is 5’11. The floor is cement. The prevailing sentiment seem to be to finish it off as is and enjoy my small home! I think that’s what I am going to do. Thanks.