Congratulations, man. That's great.
I guess my thoughts on it would be that an exhibition is like a music gig. So like a gig has a lot of purposes, but that's okay because you got a lot of songs. There are some songs you want to play just because that's the completion of the project... like you wrote that song, you love the song, and you want to play the song and have people hear it. Then there's the songs you have that might impress whatever promoter, critic, A&R person is at the show. Then there's the songs you play because you still want the audience to have a good time, and because well... the audience pays the bills.
So I would divide my portfolio up into different categories:
1) Stuff that will sell. I go to galleries and I see a lot of fantastic pictures.... of things like abandoned warehouses or homeless people or odd random shit. They're cool and all.... but do you really want that in your house? Even if there is some beauty in the picture they are still kind of depressing. No one wants to hang a picture of a homeless dude next to their Aunt Sally. So what really sells easily is stuff like babies, animals, flowers, and landscapes/cityscapes with amazing depth of field. That kind of stuff. And I would just go ahead and put those out there and charge cost plus 10% and I imagine you would still be the cheapest guy out there. Those are impulse buys. You see the pic, you know it will look good in your living room, it's cheap, you don't want to have to go find the photographer and dicker over the price. You can just go to the next gallery/booth and some guy will have a similar picture WITH price and it's just easier.
2) Stuff that is cool. This would be the stuff that you are really proud of, and you just want as many people to see it as possible. For that stuff, I would either do "name your price" or else mark it up fairly high and say "price negotiable." Because if the photo sells, then it's gone and people don't get to see it for awhile (until/unless you do a reprint and get it to the gallery, and some people are really pissy about reprints). I would just sort of want that stuff kind of on permanent display. And also, since it's a piece I feel strongly about... I kinda want some say in who it goes to, you know? If it's like a really cool person who seems really into it, I might sell it at a loss. If the person seems like a tool, they can't have it unless they pay me tool price.
3) Stuff that showcases your skill. These might not be your favorite pictures, or the most inherently interesting subject matter, but they have good technical quality. Like someone who knows something about photography might be like "How did he get that lighting?" or "Why is that in soft/ultra-sharp focus?" Because a lot of times when you go to a gallery or art walk, you're just looking for ideas. You're not planning to buy something right there and then, but you just want to see what's out there. So this way, you got some photos out there that maybe some guy might hire you on commission for a pro job (if that's what you want to do). Or a guy like me might ask you, "Hey, do you have any pictures of boats? Because I really like boats." Then you can sell me a picture of a boat or some other shot that you elected not to display. Or you can go and take a picture of a boat and sell it to me later. And that stuff I would just price at the regular price of art photos, which appears to be 10 zillion dollars or something.