To you immediate question I prefer Huberdeau. In a limited keeper [especially one with only 7 slots] prospects are often over-valued b/c of their tempting upside [which many don't reach until their 4th season]. There will also always be a plethora of top-end prospects available in your draft who simply haven't "broken out" yet.
Given some of your top end, young, and more proven talent Grigs is more than expendable IMHO.
10 Team [keep 10 + 4 prospects]
Scoring F=1[g/a]; D=2[g], 1[a]; G=2[w], -1[L], 1[OT], 2[SO] Top 12 F, 6 D, 2 G count
Crosby, Ovechkin, Backstrom, Wheeler, Byfuglien, Hornqvist, Simmonds, Ladd, Zuccarello, Ribeiro, Desharnais, Semin, MacArthur, Moulson, Purcell, Soderberg, Dupuis
Keith, Goligoski, Carlson, Krug, Trouba, Streit, Pouliot, Ceci, Nurse, Martinez