An all round good CM/DM is Lars Bender, usually available for around 3mill. LB take a look at Grimi, he's always available for under 500k or so and may be an upgrade. RB I'd go for Vrsaljko if you can gain a work permit. If not, I'd try get Aurier or maybe Gaston Diaz. For striker, I think Chramosta may be good for you, he's prolific and is available for 2.1million or try Leandro Damiao, Kevin Gameiro ( can be expensive ) or maybe Nolan Roux.
Good luck!