I don't know if I'm finding restaurants previously missed, or the new places are worth noting, or both, but here West / Northwest of Boston there are several places worth noting.
Lexington: Lexx offers comfort food done well. Khushboo is an excellent Indian restaurant, where I very much enjoyed the House Special Biryani and the Peshawari Nan.
Maynard (yes, Maynard): Blue Coyote prepares pub / comfort food quite well, and the Cast Iron Kitchen is an excellent newcomer. CIK's "little plates," like the fried baby artichoke hearts with an aioli dipping sauce, the sizzling shrimp tapas, and especially the sweet potato fries (piled a la Jenga) are terrific. The large plates, like the tuna steak and the recent special Beef Wellington are also terrific. I have yet to try either the mac 'n cheese or the beefy mac 'n cheese, but that's coming.
Sudbury: Oishii Too has been often noted in here, and rightly so. Two dishes of special merit at Oishii: the crispy sake maki with mango sauce is an incredible combo of flavors, and the cooked lobster with a spicy sauce is very special. The price is high, and you have to call the day before so they have your 2-lb. lobster on hand, but on those occasions when you're willing to spend, you won't be disappointed. For more standard fare, Sky is a solid performer.
Westford: If you're willing to cruise that way, Bamboo's sushi specials, like the salmon ceviche are excellent. I haven't tried the Chinese food at Bamboo, as I'm a sushi nut.
Groton (continuing to move further out): Filho's Cucina is a tremendous little Italian joint. They don't sell alcohol, but the liquor store accessible through a door inside the restaurant will take care of that need. Of course, the Gibbet Hill Grill is an excellent option for more high-end dining.
Concord and Acton both have many eateries, but unfortunately none are stand-outs. That's kind of a bummer as they're the closest drive!