Historically, I'm not a Frk booster. I've said before that he's probably a career AHLer, and my opinion on that hasn't really changed. I do think he'd make the season more enjoyable for me as a fan, and at this point that's all I really care about. Entertainment, some youthful energy, some new looks. I'd like lots and lots of wins, but that's probably not happening, regardless of what happens with Frk.
As for the power play and its struggles over the past couple of seasons...it's a lot of things. It's struggling to consistently gain the zone with possession and set up. It's struggling to execute a clean, crisp, purposeful cycle. It's players with good shots being trigger-shy. It's the point men struggling to hold the blue line. It's being too predictable. It's not winning enough battles. It's taking Nyquist out of a role in which he scored 14 power play goals in 2014-15. It's leaning too much on Kronwall and, arguably, leaning too much on Zetterberg.
I'm not saying Frk would hugely improve the power play. It's possible he wouldn't improve it in any significant way. And he'd probably be a liability at even strength. But a lack of right-shooting snipers has definitely been a thing in recent years and it continues to be a thing. Callahan was a grinder who never offered anything that we didn't already have in the lineup. Frk would, at least, fill Vanek's role (right-shooting specialist who needs to be sheltered at even strength).