To the first bolded, not only "healthy and available" but also familiar with the offense. I'm referring to Amari Cooper (he's been with the Bills just 7 weeks as of today) and the rookies Keon Coleman and Ray Davis. Also Curtis Samuel and also Mack Hollins are in this offense for the first time having signed with the Bills in March. All 5 of these players can be reasonably expected to more fully integrate into the offense over the final 5 weeks of the season and beyond.
To the second bolded, I disagree with you. I think the contributions from the 3 players you named could make a significant difference.
Is it clear that the Lions are better than the Eagles?