i just played against an similar team, with exact the same 3-4-3 formation, and thi team was not weak at all.
i used this formation : 3-1-3-1-2.
dl - dc - dr
dmc
ml - mc - mr
amc
st - st
dl and dr up
ml and mr up
normal mentality
passing trought the flanks
mixed passing
i won 7-1
i hope it will be helpull for you