In a H2H league, a more one-dimensional PIM player is not very valuable, as you are relying on PIM production on a weekly basis, which is not always predictable. Plus he's your second bench winger and likely won't be used that often, so there's no guarantee that he'll give you PIM when he's in your lineup.
As for who to choose, well here are Theodore and Bernier's ratios from last season:
Theodore 2.46, .917
Bernier 2.36, .909
Not conclusive, so I'd rather the guy that you know will more often than not be playing when you need to start them. Another thing is that all is takes is a slump by Halak and Elliott is in and then you are stuck with two (sort of) backups. Get the third starter at least for insurance, and if you are concerned about playing him too much to ruin the ratios, then you can try to use matchups.
All I've got...all I've got is insane!