Riflemen are too expensive for their capabilities, reduce cost to that of volks or buff them a little bit. Having access to 2xBAR is not an argument for their high cost because that requires a ton of muni and it also requires teching.
The big problem for Riflemen is that their scalability (vet and upgrades) requires a high cost, while this cost is disproportionately high for the basic performance of the unit. While I think the total costs are good as they are, I believe it would be worth experimenting around with distributing them more evenly.
In conclusion this would mean making Rifleman a bit cheaper to produce (down to around 250MP), but adding the spare manpower (of the 3-4 squads in a standard build) to the cost of the weapon rack tech upgrade. This would buff their early game performance-to-cost while retaining the current mid to late game ratio (which is already borderline OP).
Or just tone down their mid-late game (vet) scalability and lower the MP cost.