just a question. would a combination of soft (as in stock feel) shocks and stiffer (non-adjustable gas) shocks be somewhat of a good compromise for a "street fighter" car? simply, getting coilovers with soft (6-8 kg/mm) spring rates is kinda difficult albeit expensive to obtain.
Did you mean soft springs and stiff shocks, cuz you wouldn't want to mix and match shocks!
Yes, street cars or even Togue fighters ala Mt. Akina kind-a-thing favors "sport" suspension which is what you are suggesting. When you tune your suspension, you always have to consider the surface and road conditions you will be racing in. Public roads are bumpy and at times, slippery, with oil and/or water. Soft springs will provide more grip and stiff shocks will provide control. You cannot overly lower too cuz you need maximum suspension travel. I'd say 1-1.5 inch lowering is good na for Manila roads. (for circuit you need 2-3 inches!). Let me add that upgrading to larger diameter sway bars is also an excellent way to lessen the lean of your car.
Btw, 6-8 kgs springs are not that stiff pa. My Accord uses it and I find them too soft for serious track work. But they are actually ideal for the "street fighter" set-up. Well, for other cars, especially those with strut suspension, using 6-8 springs for the street may be too stiff as the effective tire spring rate may be higher due to the suspension geomery.
Generally speaking, sport suspension for hot-street is 8kg and below while circuit requires at least 10kg and above. Type R uses @4 kgs and they are the best street suspension set-up for the street in my opinion although the ride is not exactly cushy due to the stiff shocks.