Another are the level changes common to other arts that you don't find much in Wing Chun schools.
You are right. The following are missing in WC.
- drop down.
- forward jump.
- backward jump.
- body spin.
- ...
The older you are, you more that you will feel those training can keep you "young".
If we look at the following toolbox, WC can offer less tools than other MA systems can.
Toolbox:
1. Punch - jab, cross, hook, uppercut, overhand, back fist, hammer fist, side punch, spiral punch, hay-maker, ...
2. Kick - front toe kick, front heel kick, side kick, roundhouse kick, hook kick, back kick, inside crescent kick, outside crescent kick, tornado kick, jumping double front kick, jumping crescent kick, ...
3. Knee - upward knee, horizontal knee, 45 degree knee, flying knee, ...
4. Elbow - horizontal elbow, upward elbow, downward elbow, forward elbow, backward elbow, ...
5. Lock - finger lock, wrist lock, elbow lock, shoulder lock, head lock, spine lock, knee lock, ankle lock, ...
6. Throw - single leg, double legs, hip throw, leg twist, leg spring, leg lift, leg block, foot sweep, ...
7. Footwork - forward step, backward step, side step, wheeling step, circle walking, circle running, long distance advance, long distance retreat, ...
8. Ground game - full mount, side mount, arm bar, leg bar, choke, ...
9. Short weapon - dagger, double edges sword, single edge knife, Miao Diao, ...
10. Long weapon - staff, pole, spear, Guan Dao, ...
11. Throwing weapon - bow and arrow, throwing dart, throwing knife, throwing rock, ...
12. Firearm - pistol, riffle, machine gun, RPG, grenade throwing, ...