These are the 4 main reasons I can think of that would make a car feel too stiff:
1. The springs are just too stiff. Get different ones.
2. The coilover springs are poorly adjusted, and have preload. I once saw a rally driver adjusting his front coilovers to get more height. But the shock ran out of travell, and he ended up just compressing the springs till they were rock hard.
3. The shocks could be adjusted way too hard. This makes the car feel very bad, and you loose traction.
4. The shocks could be too soft or worn out, with medium or stiff springs. The same springs may feel good with new shocks.