You are going to find that if self driving, the odds are that there will not be campsites for you at that time. These started booking out months ago. You will probably need to check with a lot of 4x4 hire companies to find a 4x4 available at those dates too.
Check out the Maun Self Drive 4x4 site for info on campsites, booking options, etc. www.maunselfdrive4x4.com You may need to plan a lodge to lodge safari or mobile safari for Botswana. Or you can look at another country.

"Are there any places that a savvy off the beaten path traveler like me is missing?" Look at Zambia.

You really are a bit late to do much in the way of self-drive. Botswana limits tourist travel to keep it "less travelled." Tough on budget travelers like myself, but sometimes you can catch a break. Have you checked out &Beyond's website for some "last minute" specials? Their camps are lovely, guides wonderful, and you won't be running into lots of other vehicles. But that really shouldn't be a problem in Botswana no matter who you travel with.

Bostontravelbug,

Was in Livingstone last Nov. Visited Vic Falls and also did a day trip to Chobe National Park from there (US$65).

Even on a tour the border crossing seemed to be a pain in the butt. I imagine doing a self drive would be a challenge. To arrange a tour from Livingstone is easy and you can even do overnight trips with a night safari included.

Would definitely do Chobe

Vic Falls Video:http://youtu.be/O_nEi-tCGBA

Chobe National Park Video:http://youtu.be/_hZYg5RiYxg

"I imagine doing a self drive would be a challenge."

It really isn't. There are people that need to have things done for them, planned, and let someone else do everything. Then there are people that enjoy getting out and interacting with the locals, the freedom to do as you please, when you want, not lead around from one place to the next on a schedule. It's a misconception that a lot of people have from not doing it.

Thanks for the responses guys & girls - I really appreciate it.

In Namibia, it was easy to be off the beaten path, be remote because the land was accessible and remote doing an overland safari. On the other hand, I had heard Botswana is quite crowded in the national parks / campsites during this time of the year and a fly in to private lodges is how to do it.

I've also heard some amazing things including in this post about Zambia - should I be focused on that country as a safari option if Botswana comes in too high based on my budget?

Zambia is much easier to plan a self drive or fly-in safari. Zambia is still off the radar of most travel agents and travelers, so usually you can find a place to stay without booking 6 months to a year in advance, like in Botswana. Btw, in my opinion, it is probably the safest country in Africa.