There have been other threads on this site that have lots of information on all the types of strings you can use, so if you go there you’ll probably find more useful information than asking here. I think I started one of them a while back, so you can just go into my posting history to find it!
It sounds like the general consensus is that the new soundboard is an improvement. People who didn’t like Salvi’s are now opening up to them, and people who already liked them now like them even more. On what basis do you say that it is a step in the wrong direction? Have you played or heard one of these harps? If anything, I think a louder Salvi would also have louder overtones, thereby becoming closer to the sound that you said you enjoy.