My faves in downtown N'ville would be Tango and Hugo's. Probably Tango first. It is a particularly good deal for lunch. Some like Bistro Margot. Please do not take it wrong, but there are fairly extensive discussions on most of these places in different threads if one searches.
But I do not exactly understsand why you would want to limit yourself to "downtown" N'ville, which ala Invasion of the Body Snatchers, has been taken over by chains, albeit some pretty fancy ones.
I like Raffi's okay (is this downtown, though?), but their best thing is the Middle Eastern dishes, and the price/value equation is a little out of whack for those dishes, IMO, when you can get comparable quality down the road for cheap at Cedar Grill. The room is lovely, though, and I do miss Montparnasse (whose owner was last seen managing a bistro in Oakbrook).
I have avoided Catch 35 out of sheer orneriness, but have been pleased that Pier 34 is much less crowded since it opened and go there once a month or so, quite happily.
Since you mention Lou Malnati's and are looking for a step up, the place that most fits that description (one step up or so in atmosphere, a little more expensive, and worlds better food) is Pasta Amore over at 87th and route 59. The back dining room is pretty nice when open, and the front area is comparable to Malnati's.
Capri, up on Ogden near River, is a nicer room, owned by the parents of the guy who owns Pasta Amore, and was my favorite place in N'ville for a long time, but recent meals have not been quite so wonderful. Still, it is a fun, old school Italian spot with pretty good food. Depending on the size of your party it could be a good choice - the room is not so big, so 10-12 people is a maximum.
Lastly, I have enjoyed Sizzle India up on Brookdale quite a bit in recent visits, if you are consdering Indian.
For exquisite food in very nice surroundings, I would consider Vie in Western Springs or Isabella's in Geneva, but they are a lot more than a step or two up from Malnati's in food, atmosphere and price.
For a lot more on any of these places, just search. Google can work better than the Forum search, see Useful Stuff for "how to."
Or be a little more specific as to your requirements.
Please report back on your meal.
d
Feeling (south) loopy