I think you may have all you need to correct your problems. However, I will add one thing to the beach start - make sure you have enough wind before stepping up. Sometimes you may have to wait a minute or two for a gust, otherwise because of the big step, you won't have enough power in your sail to pull you up far enough to get to the center line and you will fall back in. Even the "good guys" fall back from time to time when they are anxious to get going, but there isn't quite enough wind to step up.
If there is too much wind, getting up is easy, but you don't want to be pulled off the other side either. Using full power to get you up and then sheeting out at exactly the right moment will keep you on top. This technique is the same for learning water starts when in strong winds, so don't be afraid to practice beach starts when it is windy.
Be sure that you are in deep enough water, or your fin will pay the price. A new fin will be costly!
Formula 160; iSonic 111; HiFly Move 105; Tiga 263; '85 Mistral Superlight.
Maui Sails TR 11.0; 9.2; 8.4; 7.6; 6.6; Maui Sails Switch 6.0; 5.2; Maui Sails Global 4.5; 4.0.