Welcome, lillib. I am fascinated by how you have "mostly integrated" but have held on to a few alters. you say you still need them though, so it makes sense that these last few have not integrated. Me and my system have integrated a couple of parts, I believe, but there are some I simply couldn't imagine being without.
We have an expansive internal world where the alters "live" and the more we discover the more I believe we have quite a few very fragmented alters too. It is so sad that young children can be so damaged by the very people they rely on for life. ;(