You should be able to plane in 10 knots with the 122 and a 9.0 sail, if you have good pumping skills to get going. 10 knots is just about the bottom end in my opinion for you to plane. If you sail into some 8 knot holes, you will drop off plane if the hole lasts for more than 5-8 seconds.
The 122 will be pretty big and difficult to control in 20+ knots. Up to 18-20 you should be ok with the 7.0, but over 20, it will be very challenging. Even with a smaller sail (6.0 or 5.0), in winds over 25 knots, the board will be too large for someone that weighs 75kg.
In 20 to 30 knots, most sailors your size will be on boards from 85 liters to 100 liters depending on their skill and their sailing site (variable winds sometimes require larger boards). Salt or fresh water plays a role too.
It's essentially impossible to have one board that does it all (10-30 knots), but the 122 is about the best you can do.
Hope this helps,