My policy has always been...
Every 100,000 miles replace every bushing, bearing, and ball joint on the car to keep it driving like new. Since the non M parts are so squishy, good chance to upgrade them to M parts effectively for free.
Idlers/tensioners/pulleys/belts and the entire cooling system (radiator, thermostat, water pump, pipes, expansion tank) to keep it as reliable as new.
And if you really don't want to risk a breakdown, since filters are replaceable anymore... fuel pump.
Spark plugs are an inspection 2 item, imo, so unless you happen to be coming up on that for the second time as well, I'd skip it. Same with diff and trans fluid. Though, that assumes you haven't been skipping those things until now...
Sending the fuel injectors off for a rebuild is cheap and probably not a terrible idea at 100,000. Likely at least partially clogged by now.
I haven't seen any instances of leaky valve cover gaskets on the N52 yet, but it's pretty hard to imagine it going to 200,000 without leaks... so I might do that too, while everything was getting done (along with the ones for the bolts that hold it down and around the spark plugs).
Pre cat 02s to keep the engine running as efficiently as possible.
Every 100,000 miles is the most expensive time in a BMW's life
if you want to keep it driving like, and being as reliable as, a new car. Do all that and you should be nicely locked down till 200,000 with just fluid changes
