There are tons of options for hotels in Vegas at all different price points. Go to
www.caesars.com and put in your dates to seee the rates you can get at all the Caesar's owned properties (Caesars Palace, Planet Hollywood, Cromwell, Paris, Bally's, Flamingo, Linq, Rio and Harrahs) at the same time.
Strip options that I would classify as being "between" NYNY and Venetian are:
Mandalay Bay, Mirage, Monte Carlo, TI, Planet Hollywood, Paris, Bally's and MGM. (I would put Cromwell in that category also - but they price it higher than it is worth - also FWIW Cromwell does have a casino not sure why the above poster did not think it had one).
Places that are on par or above Venetian/Palazzo in qualifty would include - Aria, Cosmopolitan, Bellagio and Wynn/Encore.
Caesar's Palace is difficult to categorize because room quality varies greatly between the towers. The newer nicer rooms (Augustus or Octaviou Towers) I would rate above the Venetian, but the Roman Tower rooms will be similar to NYNY.
Time of year makes a difference also as you might want to take into account the quality of the pool facility if you are there in the summer - that varies greatly between the properties.
In terms of value for the money for room quality I think right now Bally's is a good deal. Their Jubilee Tower rooms were recently renovated and are nice. Flamingo Go rooms are also OK for what is usually a relatively cheap price. I don't particurlarly like either the Flamingo or Bally's casinos - but they are centrally located so you have lots of options for gaming in other casinos. Check out the rates that you can get for your dates and I if you want I would be happy to give you my thoughts on the best deal depending on your budget. I have stayed at most of the strip properties at least once.