I really like the CSL style wheels, so I'm diggin' your car already. I am going a similar route (TSW Nurburgrings) and decided to go with 20" rims all the way around. Part of this is because I am limited in the rim width, correct offsets, and bolt pattern. However, I do prefer the look of a larger wheel, so 20" is where I draw the line between sporty and ghetto. My advice: decide if you want to see more rim or more tire. Then, check out rim widths, offsets, and bolt patterns to make sure Forgestar manufactures the rims you like. You may also think about sidewall flex, but 19" tires are more than ample and probably don't exhibit much more sidewall flex than a 20" tire. Lastly, check out which tires you plan to purchase. This could also influence which route you go, as it did with mine (Michelin Pilot Super Sports).
As for the suspension, I'd go with a 1.5" drop if your area has decent roads. Where I live, the roads suck pretty bad, so I wouldn't want to go much more than a 1" drop (Steeda Sport Springs).
Good news? You really can't go wrong. The F14s look great in both 19" and 20"s. The same goes for a 1" or 1.5" drop. What you're asking very much boils down to preference, so I hope my words helped persuade you one way or another.