It won't take much of a difference... I made a door guide, you can take a look [Here[(https://www.houzz.com/photos/door-height-guide-new-york-phvw-vp~44990094) maybe you find it helpful.

Good luck

Nice if you can do it as it just adds to the height of the room, but you need to look at added cost and see if it fits your budget. May not be worth it. There also may be other areas where that money spent will show better.

We are doing 9 ft ceilings but standard 6'8" doors. If I were you I'd call you're local supplier where you intend to purchase your doors and get some prices. We went standard for cost and ease reasons. You may have a hard time finding 7ft doors at a big box store. We bought a 6'8" exterior door with a 6 inch (instead of 4inch) jamb and it was a special order. Just make sure you'll be able to find the style you like if you go 7ft. Plus we wanted to spend our $$ on wood, not composite, so that helped offset the cost.