First of all, congratulations! And welcome!
Being a cruiser rider, you are used to coming to a stop and having some bend in your knees while both feet rest flat? Those days are over, for sure. I am 31" inseam and in many places am doing a ballerina tip toe to reach the ground. Let me tell you this right now... you do not, you DO NOT, have to have two feet flat on the ground when you come to a stop. That's a fallacy perpetuated by the cruiser crowd. :-)
One big thing to pay attention to on your first, LONG ride on a tall bike is when you are coming to a stop, whether a stop sign, stoplight, whatever...look ahead before you get there and check to see if the road is flat. If it is, proceed as usual.
If the road is crowned, IOW, tapers off to one side or the other, use the foot on the HIGH side to put down when you stop. If you use the low side foot, a tip over may be in your immediate future. This goes for almost any bike but on taller bikes like dual sports, it's just something else to take notice of.
The first or second time you don't notice it, and after you change underwear, it will soon be second nature to scan ahead for the pitch of the road.
And don't ever worry about always having to use the rear brake to hold yourself on a hill. Your right index finger draped over the front brake will do just fine for you if your right leg is busy holding the bike upright. :-)
Good luck, TAKE YOUR TIME and ENJOY that new ride!
PS-- I've always been lucky....most of the sales guys I've bought from over the years were very, very experienced riders and I always received good intel on the bike I was riding away from the dealership on.
In fact, my '13 DL 650 (just over a month old now) was purchased from the same salesman I bought my first Beemer from in '92! He's at a different dealership now and before I bought the DL, he reached in his pocket, tossed me some keys and said "Take mine out for a spin first, Pat". Yeah, he has a DL 650 too.
So don't count on your salesperson NOT being able to give you some tips. If he, or she, can't, ask to talk to one of the technicians. Most of them ride outside of work, their work does put them on scads of different bikes to test ride after service, so they too can be a valuable source of information for you who is new to tall bikes.
Again, good luck!!!