I'm trying to figure out where those 16g of carbs came from - was it mostly the sauce? You should be able to find a lower-carb sauce than that. I buy a store brand ("Simply Enjoy") pasta sauce (which they carry in multiple varieties: marinara, garlic, vodka sauce, etc.) that only has I believe 4g net carbs per 1/2 cup.
Personally, I don't limit my fat intake at all - if you're eating low in carbs, fat won't hurt you. It's the combination of fat and carbs that ends up sending cholesterol out of whack and clogging arteries and all the other evil stuff that fat gets blamed for. So, against most dieticians' recommendations, if the fat doesn't make you feel icky (I know some RNYers who dump on high-fat foods), I wouldn't worry about it. I also never count calories since, again, they're less impactful when eating low in carbs - I can lose weight on 2000 calories a day of low-carb, high-fat foods, but if I add carbs back into the picture, I have to much further restrict my calories to be able to lose.
When I want something Italian-ish, I mix my jar of pasta sauce with LOTS of MEAT - ground beef or turkey and maybe even some sliced up Italian sausage - and then eat that with melted cheese on top. You'll get more protein than with just cheese and sauce when you add the meat in there, and you'll likely end up eating less sauce overall when it's mixed in with the meat. For a veggie kick, also good to add some frozen chopped spinach - can't really taste it, but if we learned enything from Popeye, it's that spinach is good for us! Plus it can also act as a bit of a bulking agent that will also help to cut down on total portion sizes for the other components.
If you're feeling like spending a little time in the kitchen, I LOVE this stuff:
http://www.genaw.com/lowcarb/spinach_lasagna.html (I make mine more like the "variation" on the bottom - more meat, more sauce, and more cheese, and then I have a whole pan of it to last me all week!)