IMO:
Personally i think 2 oscars to a min 90g. by themselves is adequate.
being a 120g tank is not alot bigger and i believe the combo of fish you have listed
may be overstock for that tank.
i know Oscars,JD's,FM's can all get along (temperments pending), but to have a pair of each in a 120 i believe is too much.
Depending on which fish you like the most i would go with a pair of them. and maybe 1 of the others.
I think 2 JD's and an Oscar would be pretty cool (im not big on FM's).
you could probably get away with another fish or 2, maybe even what you listed, but it would need massive filtration and a strict, well maintained PWC schedule.
I have 2 Oscars in a 90g, albeit they are only 5" now, when they are full grown they will dwarf the 90g.
i have an AC110 and a Rena XP3 on it & 30% weekly pwc , even though it is adequate iam going to add 1 more AC 110.
Adequate Filtration=good,Overfiltration=best.