Tolkien seems to find a number of reasons why Glorfindel was reincarnated (being under the ban was problematic). He didn't list them like this, but here goes:
1) Glorfindel was an Elda of high and noble spirit (I'm going to assume exceptionally high and noble is meant)
2) he incurred the ban reluctantly only because of kinship and allegiance to Turgon, and love for his Kindred.
3) he took no part in the Kinslaying
4)
'More important': he had sacrificed his life, enabling Tuor and Idril to escape, a deed of vital importance to the designs of the Valar.
So Glorfindel was purged of any guilt (in note 12 Tolkien describes that his guilt had been small, and once again refers to his noble character, among other things), released from Mandos, and Manwe restored him to bodily life -- and he gained the primitive innocence and grace of the Eldar. It is then said he became a friend and follower of Gandalf.
Of course much of that's been already covered, but not in list form
