the mosfet noise included thermal and flicker noise , for thermal noise it is hard to
reduce , for flicker noise u can use large p-mos. Most CS noise is power noise.You can use cascode CS.
Increasing wl can reduce flicker noise, but it will also increase the parasitic capacitors. So there will be tradeoff.
Using cascode is Ok, but it will consume more voltage margin.
You can refer to Analog Cmos IC Design chapter 7.
Add a small inductance in series with the current source. The bias stays ok, but as frequency increases, the effect of the current noise source reduces