Valve clearance check once a season, suspension refresh once a season (depending on mileage) all bearings greased once a season, calipers cleaned every weekend, brake fluid flush twice a season.
All sounds good.
Add to that:
1.) Check bolts for tightness every day.
2.) Keep the battery on a tender
3.) Lubricate the shifter and brake levers a few times per season, especially after rain events.
4.) I like to take the air filter out every couple races and beat out all the bugs and tire chuncks stuck in it. I clean it with the cleaner twice per season.
5.) If you're running straight water + water wetter, flush it out once per season. Stock stuff, just run the recommended manual length.
6.) Spark plugs I change at the recommended manual setting or once per season, whichever happens first.
7.) Check your brake pads daily. As you get faster, you'll find those wear out a lot quicker and quicker.
8.) You'll also want to check your chain length more regularly. It will stretch quicker.