A couple of things...
1) There is no need for a second pump for the steam boiler, a 2 way solenoid would be better.
2) a pressure stat will be better for the seam boiler.
3) if you want precision in brewing temp, you want a PID.
4) doing what you plan is massive job that requires a lot of technical knowledge, especially in electronics which by the questions youre asking make it sound like you dont really have - at least yet. I would advise against it , but if you insist, a lot of research and learning will be required.
5) its spelled "espresso"