Not a lot of choice for fine dining or exotic lodging, to say the least, LOL, but the view from the rim drive around the lake up at the top is WELL worth it - you won't be caring much about food for sure.
I love Crater Lake NP - it's small for sure, but not very crowded, and while there aren't a billion things to do like, say, Yosemite or Glacier, it's one of my favorites. Something about being there photographing before sunrise (in which case you're likely the only one there) in the absolute dead quiet of morning really gets me - there's a peaceful calm about that lake that reminds you that it was around long before we came along and likely will be long after we're gone.
As for shooting - sunrise and sunset for sure. I seem to remember that I enjoyed locations (up on the rim drive that circles the crater) near the rim-level visitors center and lodge as well as a location roughly opposing it on the north side of the rim. If you've got the time, shoot in multiple locations - picking one spot for both rise and set one day and then another for the next.
Watch out for crazy RV drivers going around the curves too fast - the road is a bit narrow in a few spots. Other than that - enjoy yourself.
I haven't been on the lake tour but I'm sure it's worth it.
And yes, the lake really is THAT blue
-m