Yandle was a long-term PP QB who had a lot of success in that role.
Even this season, his worst in 6 years, he has a xGF/60 of 7.00, xGA/60: 0.96.
For comparison, Ghost the last three seasons, xGF/60: 6.28, 7.24, 6.24, xGF/60: 1.06, 0.62, 1.39
His first four seasons Ghost was an elite PP QB before he started to fade (and the talent around him deteriorated).
I don't think Sanheim has the skill package for PP1 QB, of all our D-men, only York seems to have that feel. Ellis would be a good pairing for Sanheim at PP2, he's not a great driver of play on the PP, but has a very low xGA/60 over his career, suggesting he's a careful QB who knows how to CYA for a partner. Sanheim just doesn't look comfortable near the blue line, in a "stationary" role, he's at his best flying up the ice, pressuring the defense.
Attard has a better shot and is a RHD, so I'd have him on the PP as a partner to a LHD before Provorov.
Why they have TK in the net front position is beyond me, though Allison might replace him next year until he goes on IR.