first, DON'T undervalue your work. it doesn't matter if you don't think every shot is an SI cover...for most people, seeing someone in jersey, playing or not, means the world.
second, take a look at what your peers are doing. if there's no one else shooting and selling, look around at similar leagues elsewhere. find their websites, shoot some emails, make some calls. one thing you don't want to do is way undercut the market. even if you "own" your market (ie, no competition), you still don't want to establish yourself as the give-away guy.
next, look at this from a business standpoint. to be fair to you (and your wife), think of ALL the time (attending, shooting, selecting, processing, archiving, etc) that you have put into this so far. just for grins, let's say you've got a total of 50 hours in it. let's say (conservatively) that your cost of business is "only" $30/hr. to break even, you need to make $1500. now it gets tricky. how many players are involved? you'll need to play with some numbers to get an idea of what type of product mix and pricing could get you the sales necessary to hit your break even number.
consider some things you can do to maximize this opportunity to sell. if you have already gone through all the images and have 800 of them ready-to-print, you are way ahead of the game. you could offer single 8x12 prints for $20, or the high-res file for $25, or the low-res file for $5. you could offer a single game disk or a single player complete season disk (with a guaranteed number of images) either low-res for $25 or high-res for $75. you could offer the whole season low-res for $100 or high-res for $250. (the key is the number of games you shot.) lastly, you could offer some high-end edits to make commemorative poster-sized prints. there are plenty of inexpensive templates (some labs offer them for free) for making mock magazine covers and such.
again, while you as a photographer might not think an image is that great, someone else as a parent might think you have captured the iconic shot of their kid and might be willing to spend a couple hundred. you never know. i captured a killer shot of a kid smashing a grand-slam homerun in his last at-bat in college baseball and his mother told me i was ripping her off to ask for $20 for an 8x10. i've had other parents spend $1-2k, buying any and every shot i took that they could identify their kid's jersey number. all i could do was guarantee that if they weren't thrilled once they got their purchase, i'd take it back, no questions asked.
i know time is short, but don't rush yourself to just give away the store. take some time to figure out some options that will let you create a win-win for everyone (including your wife!). one other thing to consider is to get an online sales account (like at http://www.exposuremanager.com ). set your prices slightly higher and offer your on-site sales as a discount off your normal prices. just have some flyers (even half-pagers) with your contact info that people can take home. that way, you can get some sales immediately as well as residual sales down the road. (along these lines, have a pad and collect email addresses from as many people as you can, if you don't already have them.)
hope this helps, good luck!