Welcome and congratulations.
you'll get a ton of recommendations but there are literally hundreds of mods and upgrades and which ones are important to you is hard to tell from here; it really depends on usage, expectations, experience and budget.
For eg. I ride my KLR's offroad extensively so protection (skidplate, handguards, rad protection), control (bars, pegs) and performance (suspension and brakes) are the most important mods for me. Conversely, someone commuting or using thier KLR for longer pavement duty consider things like taller windscreens, crampbusters, aftermarket seats and panniers to be important....where I want none of those things.
....and sorry, it's still the same old "doohickey" since 2008.