The D200 has a 8gb sandisk limit. Get an 8 gb or less and it will be fine.
I believe the D7200 has the Nikon Lighting System built in with the pop up flash. Use the pop up along with the SB800 on a off camera slave on a tripod/light stand for fill on those lover shots. Practice off camera slave flash with you tube videos before you go. 90% of pro photographers use an off camera flash.
Look at the Tokina 100mm f2.8 FX macro lens. It's rated higher than the top 3 competitors and is only $340. I got one and love it! Great for macro and portraiture.
Move the exposure comp button and watch what the settings do. That should answer your question.
If you shoot RAW you have to post process.
I just bought a new one of these. I love it! It gets you out as wide as a crop sensor will get you with little distortion. Tokina is a great Japanese manufacturer that build lens as tough as a tank.
I would have to disagree with you on this one. My D500 VR is activated when ever any of my programmed buttons that are set to AF-AREA MODE + AF-ON are pressed. I shoot in continuous mode. Part of BBC is continuous mode. You can single press to lock focus or hold the button continuously to follow focus a subject. My VR is working all the time. Of coarse the new Nikon fast focus system in my D500 my be part of it. This system works with all their new fast lenses made for this system. The D500, D850, and the D5 have this system.
Oh, that's a big question. If your computer has it's video card built in the motherboard and you have an extra or open pic slot then yes you can upgrade.
Yes Tokina 11-16MM f2.8 is my choice too. Built like a tank made in Japan and very sharp. I also love my Nikon 16-80mm f2.8 for my over use lens. I have a D500 crop sensor camera also.
They don't want to get sued. Try carrying it and see if it will hold tightly. You will know right away believe me.
Watch Mark Smith videos on you tube. He is great and will help you with camera settings (focusing birds, auto ISO, manual mode, back focus button, ect.)