i think you are getting good airration with that mix, a little perlite wont hurt, be careful though that mix can dry out very very fast going from green to wilt very rapidly
i'm using this same mix and haven't added any extra perlite.... seems like it drains really fast... i'm a few weeks into veg and i water about once every 2 days, sometimes i water just a teensy bit on the offdays.... overall i think this mix is great for the price with the Mycorise already added