Congrats on the new bike, I think you and your son will really enjoy it, and tell your son I said thank you for his service, I ride both with my son , daughter and father, it's one of my greatest pleasure in life, i was not really close to my dad when I was growing up, he was always busy with the Highway patrol, but in our older years, bikes have really brought us together, and the bonds I'm forming with my own kids will last a life time, and I'm sure the same will happen for you and your son, way to go Dad!
I bought my 17 year old daughter a 06 SV650S for her second bike, she did a year on a Ninja 500 first, Now by no means is an SV any where close to a Ninja 636, but it's probably a better bike for your son to be on any ways, not too much power, pretty torquey for real world riding, and it's different, every one has a CBR or 636.
We put a few extras on my daughters bike and have done some mods to fit her better, every where we go people come over and ask what it is, some have asked if it was the new GSXR, and with the Yosh pipe, full lower cowls,it sounds like one bad ass lawn mower!!!!
On our daughters I made a fender eliminator for it, added the rear hugger, seat cowl, Yosh pipe, full lower cowls,Stebel horn, Stainless front brake lines, ditched the passenger foot peg on the LT side of the bike, and in the second set of pictures you can see we converted it over to the naked model style of dirt bike bars, and got rid of the clip ons, for a 650, it has a long reach to the bars and my daughter Ashlie was just too spread out on it, I think she will be much more comfortable and safer on it now since she'll have better control of it,
And to think it looked just like yours when it was new, there's allot you can do to an SV.
After converting to dirt bike bars, oh and my daughters customizing with decals. notice how much higher the bars are now,