First off, I admit my 45 years of clutching conventional 4/5 speeds may be counterproductive to my STI, but to me the friction zone of the STI's clutch is among the lowest I've experienced. Muscle memory from other clutches had me not depressing the STI clutch pedal far enough resulting in synchro blockout while changing gears. Sad to say, but it's taken me about 15 months and 8000 miles to instinctively get it right. I've not had any clutch disk burning scent, but I'll admit I've missed shifts.
A couple more observations. The short throw shifter has gotten much freer as the mileage progressed. The engine has too and has become much less susceptible to increasing clutch load (that is, killing the engine). The 2.5 is among the quickest revving engines I've had (even in I mode) so getting used to that is part of my 15 month slow learning process. I've had to experiment with best driving position/coordination. Much of this may be due to my old slow neurons. Someone mentioned many months ago that reaching about 2000 RPM as you traverse the friction zone worked well. I find that to be roughly true (1500-2000 RPM for me). This is assumes level ground. I also have found that I can anticipate the hill holder delay feature pretty well.
Hang in there, you'll be fine.