Many coilovers and aftermarket springs are stiffer in the front; I wouldn't necessarily base my decision on that. Read people's reviews to see what they say. For instance, Ohlins R&T is stiffer in the front. RCE and KW are square. Some of Swift's springs are actually stiffer in the rear.
Go through this thread; there's a lot of good info here.
http://www.ft86club.com/forums/showthread.php?t=45554
To fit 18x9.5, read this thread. Clearance in the front can get pretty tight.
http://www.ft86club.com/forums/showthread.php?t=41083