This video clearly explains the anti-lag feature improvements needed for FH5. The current anti-lag exhaust flames are just not realistic. They are super static, have only one color & size for all cars, and fake-looking as they do not even protrude properly from the exhausts; in comparison to Gran Turismo and NFS (both of which have very realistic, unique and proper flame system).
In addition, we are currently limited to adding anti-lag only with race turbos. There has to be better way to implement anti-lag, especially on cars that already have turbos to prevent moving up in performance class (say A to S1).