Given that it is 2035, any of the helicopters (except maybe the Pawnee/hummingbird, due to weight restrictions and likely employment) should definitely have Missile Warning Receivers and Radar Warning Receivers. The Mohawk model actually has MWS blisters on the nose and tail, so removing that feature is a bit naff.
I support the radars being removed from the helicopters though. I'd suggest this should be removed from the Blackfoot as well, as the planned implementation of the radar was a Apache Longbow setup above the main rotor. I acknowledge if the radar must be included to get DAGRs etc to work though.
A better solution would be to reduce the effectiveness of flares or just have a bit more fidelity on how they actually decoy missiles. I'm pretty sure IIR missiles (that is, Imaging IR.) aren't actually decoyed by flares anyway.