There's a ton of different ways to look at who slots where and how competent they are in that role. Ottawa needs to focus on depth since our top end talent will never be in the same category as teams like Colorado, Edmonton, Toronto, Tampa, etc. Fortunately we have excellent center depth which is huge, competent goaltending, and a true #1D. When healthy, Ottawa has 4 guys that are slightly above average top 4D, but the forward depth is sketchy once you start getting past spot 7, and that's including Giroux who's a question mark moving forward.
Zetterlund is a good add to address that, I just don't think he is in any way a good top line option. I think an aging Giroux would still be better next year. Getting a top line player in the off season would be near impossible without mortgaging the future in terms of money, draft capital, or losing a good asset on the roster. So we need to probably look at spending on bottom 6 guys to ice a roster more comparable to Winnipeg or Washington. They win a lot of games because they can roll 4 lines and not worry about their top guys always having to shoulder the load, while having confidence their 4th line won't get caved on the road when they're stuck out there against the home teams assassins.
Paying Zetterlund top 6 cash will lessen our ability to go with guys like Amadio, Cousins, or a Nic Dowd to fill in the bottom. If Giroux stays and still wants a decent paycheck, can we afford handing out $9M+ to him and Zetterlund? Zetterlund is still RFA, he can sign a one year show me deal if he feels he's worth more than $4M long term. Grieg is a better player than him now and signed for 4 years at $3.25M. There's no way I'd be comfortable giving Zetterlund more than that under any term right now, he's still a question mark.