Thanks for all of the input.
There will probably be 6 to 12 people going on this trip. Our Derby roster this year dropped from 12 to 9 within a couple days of the trip, so I don't want to try a priceline bid or any kind of prepaid rate. This trip should be a little more firm come March/April since air travel will be involved.
It would be great to stay in the inner harbor area, but I don't think the prices will work out for anyone's budget - unless we fit 12 people into one room.
Thanks for the input on the HI by the stadiums. I'll drop that from consideration.
For now I think I'll book something out by BWI with access to the light rail. I notice several hotels advertise free 24 hour shuttles to the rail station. Are there any with direct (walking) access? IC and SPG properties are my preference, both for points and my corporate discount there.