I’d concentrate big time on the centre than wing. The best 3C we can get turns us into a 4 line scoring team with the wingers we have right now.
Agreed. If the last few years should tell you anything, it's that the Pens have a ton of wingers that can play well with quality centers. ZAR was an unproven prospect with moderate upside not that long ago and now looks like a legit top 9 player. That doesn't mean he's a stud, but he can be effective and productive with Crosby. Ditto Simon, Sprong, Sheary, etc.
Pens have the following wings that can play in a top 9 role:
Kessel, Jake, Hornqvist, Rust, Hagelin, Sheary, Simon, ZAR, Sprong.
The Pens have 3 top 9 centers and virtually nothing after that.
Go get your center and if you've subtracted too much depth at wing to do it, then bring in a rental winger to fill the gap.