this is the 1st time im hearing that yokos are.harder than dunlops.it'll be a great learning for us if you can mention any particular model coz ive always found dunlops to be a bit harder in comparison
Civic have stiffer suspension as compared to other cars in 1200-1400 kg car category. Go foe something soft such as Yokohama Aspec, Lemans etc. Size I think 205 mm width looks nice as compared to 195.
I would recommend u to go for Yokohama C Drive with 205-60-15 (if u want to keep the original height of ur car). 205/65-15 will make ur ride a little higher. I am using C drive in my car and its a wonderful tyre.