Reproducible/correct setting of exposure - portraits?

[bimpatiens]

Hi
I just switched to another photoservice. I found some prints which, when printed, showed to be very very dark. Here's an example. The photoservice corrected one..However, I didn't care for the 'broad brush' lightening of the entire photo which the photo service did.. and, this approach is dangerous, as it removes some degree of control.

I would rather correct my errors!!

Two questions come to mind -

1. How can I set some sort of reproducible standard for skin 'brighteness'?
2. Hhow can I tell ahead of time that a print will come out too dark (they look fine in the monitor, which I have calibrated ).

Thanks so much!
This was not lightened:


I've selectedly lightened this one.



While we're 'at' it, what else might be done to improve this image in post processing?