The reflectors are such a mute point. Go buy some painted replacements for $80 in FifthStreet's group buy.
Roughly a 30% discounted price compared to our European friends and you don't want to spend the extra $80 to get around having the ambers. Its such a non-issue, its ridiculous.
As for the seats, I bet you don't even know what you missing. Its not like you currently have those Euro spec seat cushions and will miss them.
Personally, even with a launch control available I doubt I'd use it that often. I'd rather launch it myself and enjoy it, not just sit along for the ride 'til 60 mph.