I can't imagine Lucas getting cut if Ike made it back.
I refuse to believe that Lucas, of all veterans, would be cut. I just can't fathom how anyone on the SSB team could look at the Brawl roster and say "Hmm, so you know who shouldn't make it into the next roster? Lucas. But Toon Link is okay. And three Star Fox characters is absolutely perfect. But no Lucas, no one likes him."
Let's count the games they've been in, not counting SSB:
Lucas:
1? M3
Ike:
3? PoR, RD, A
Toon Link:
7? TWW, TWWHD, FS, FSA, MC, PH, ST
Falco:
6? SF, SF64, SF643D, SFAdv, SFAs, SFC
Wolf:
4? SF64, SF643D, SFAs, SFC
Now let's count the games those characters will likely appear in, in the future, not counting SSB:
Lucas:
0 (Series creator says series is over)
Ike:
1 (Seen in Shin-Megami Tensei X Fire Emblem trailer)
Toon Link:
Several (Very popular series)
Falco and Wolf:
A few at least (Quite popular series)
Seems fair to me.