Seat is adjustable.
Springs are a bit soft if you ride two up.
Bar clamps can be rotated 180 to move bars for taller shorter folk.
Tall folk need a small screen extension to get a quiet air bubble
Get the riders manual and READ it, there are soooooooo many knob question that would have been answered it the manual was looked at.
Service it yourself .... it isn't difficult, see under 'youtube', keep records, honestly it won't hurt resale, and you'll know it has been done properly.
Get a 20-100nm torque wrench.
The bike has a dry clutch so car oil is ok for the engine. Change it at 10000km. Pay the extra and use synthetic if you'll have the bike for MEGA mileage
Rear hub and gearbox oil at 20000km read the manual for spec of oil. 180ml in rear hub.
Change the air filter so you know it is good, the std paper elements flow way more air than your engine needs and filter mega fine dust.
Spark plugs will go a fair distance, Iridium plugs seem to keep their edge a LOT longer - but cost more.
Get the bike warm and check the throttle body balance at 3500-4000rpm......get 4m of tube, cable tie to 2m plank so you end up with a 2m u-bend, half fill with some oil (doesn't matter what), plug in the two loose ends into the side of your throttle bodies, should be even oil levels in the tube.
ABS pumps can fail and normally it is a sticking 12v motor brush on the abs module, there are threads on the web how to fix em.
There is a ECU interface tool that lets you read error codes and reset service reminders and and change instruments and things - GS911 - it'll pay for itself if you don't go to a BMW shop!
Do not, Do not, Do not !!!!!......ever idle the bike to 'warm it up' - first the engine does not need it, second many people have melted(fucked) their bike!
Set the front and rear preload with even sag roughly 30% when sat on the bike.
Stuff will wear out or break, don't panic and start moaning. Please.
Tyres - there is no 'right' tyre, buy some and if they are wrong.... wear'em out and buy different next time. Read the manual for size and pressures.
Read the riders manual.