So on an average track where your pb would be around 1:30 your setup is giving you about 30 secs advantage over a bad setup?
I'm sorry but I don't quite agree to that.
I'd say more like 5% (would be 4,5 secs on that given track) could be gained with a setup, if the previous set was at least a half reasonable one (say race_s for example).
That's weird cos it seems to work for everyone else. It's a difficult task making quality skins so don't rush it. You have a excellent base there and I'd hate to see it ruined by a few rushed decals.