Can I second what ZoltanJr says? it would be fantastic if you could share your current Alembic code; perhaps we could collaborate to develop it further and possibly share it more widely? Our application area is using UE4 for cinematics, and Alembic is fast becoming the standard for the VFX industry.
BTW, how did you find the streaming performance? We did look at Alembic support in CryEngine, but found that the streaming would get constantly out of synch with the rest of the level, making it fairly useless for making movies… would be interested to hear if you had similar issues.