I might be in the minority, but I really like the ending as is. The only thing I would add is Force Ghost Ben Solo.
I agree…all I needed was Ben showing up as a force ghost at the end to join his mother and uncle. I also wish Finn had of been there to imply he would be Rey’s first Jedi student. However, I don’t know how you would imply that with the material we currently have unless it was audio off screen because the sequel trilogy doesn’t have enough of Finn yelling “RRRREEEEYYYYY!”