Your mechanic has suggested a schedule for a different car. 30K tranny services will get expensive if you drive the car. The feeling on the 722.6 is that the tranny will easily go 50-60K miles between services. You need special MB fluid, and the fluid temp must be 80C to check the level, dipstick not included. Generally runs $250-300.
On your A services, you should change the oil/filter, cabin dust filter, and probably the engine air filter. Do them when the FSS counts down. Change the oil more frequently, most people think 3-5K miles with Mobil 1 about right.
The M111 kompressor engine has frequent plug intervals, check your service manual. That's the MAX they will live.
Why bleed the brakes so often? Are you having problems?
1998 C230 "Black Betty"