Most sport oriented seats, adjustable or not, are setup this way because usually you want at least a little bit of support for your thighs and it also keeps you in the seat. Personally I don't think having the front lower than where the bottom sits is a very good driving position, but if it works for you...the best angle of course is a factor of how close to the wheel you like to sit and the length of your legs. Basically you don't want your thighs to have a lot of air underneath them.
A note on the Reverie seats - in some ways they are more confining than the stock seats. If you have broad shoulders, then you might experiment with using or not using the padding kit. At a very svelte 6' 185 .lbs, I find the shoulder area slightly constricted with the back padding in, and just about perfect without the padding. The shoulder situation is similar to that in the Porsche sports seat. Better when your arms are extended, as when driving, and slightly more snug for a passenger. The bottom padding I would leave in just for comfort.
As far as the bottom area...I would definitely get the measurements or sit in one first. If you want to go wider, Shinoo may have something else in the works for you as well.