Lace looks so much improved when you can block it well, that is why wool is so nice for that sort of project. I don't know that the lace will get opened up so that you get the full effect of the nice pattern with a blend. I wouldn't recommend steam unless you would like the yarn to get limp. I think if you steamed it it would help the lace to look more finished, but you have to balance that against the way it will make the material go limp.
I made a lace scarf with acrylic and steamed it. If you steam the acrylic I understand that it will keep the blocking forever, but it will make it go limp. I wanted my scarf to get drapy and that worked perfectly, but think carefully about what you want to happen, because there are no backsies with steam and acrylic. The yarn actually melts a bit (or a lot if you are not careful). Try a sample swatch with a lace pattern and your yarn and try blocking it just with water and then if you don't like the look of that try steam and see if you like the result.