A few things to keep in mind with an Altered. Make sure you get a good burnout and very important make sure you are pointed straight down the track and in the groove. Once you get out of groove it can get ugly quick. If it ever does anything stupid just get out of it and let it settle completely down. Most of crashes I have seen were because they got back on throttle after getting out of it. One of the other things is just get out there and make laps, run every race you can to get good competition seat time. It is a whole different animal than a door car and you will learn a lot.
On my car and probably many other Altered leaving soft does not cut it, the car wants to walk around. Just does not hook up right. I have to line it up good and hit it hard, then it plants rear tires, transfers weight, brings the front end up a little and hauls butt. Rear tire pressure is critical as on mine it is riding rear tires for a while. Your car runs similar to mine so if chassis is set up right should not be too bad. At that speed and faster a rear wing really helps, faster you go smoother it rides. You can run with out a rear wing but after you put one on there you will probably never run with out one again.
