The horse-drawn carriages line the cobbled street beside Independence Hall, waiting for their fares in the evening mist. It is, no doubt, one of Philadelphia's most timeless scenes.

Except this time there's a pleasant new wrinkle: a cold cocktail with bourbon and amontillado sherry rattles in my hand as I spy those coaches through the tall windows at my mezzanine perch in the Red Owl Tavern. And I'm not waiting for a historic tour. I'm hoping for my dinner, a feast of house-made sausage, roasted marrowbone, and creamy pot pie.

The meal - and my subsequent visits to the Red Owl - wouldn't turn out exactly as I'd hoped. But that does not diminish the significance of this new arrival and its genuine ambitions.

It's been generations - surely before Ed Bacon's vision of Independence Mall was created - that an actual restaurant fronted these historic greens. And it is long in coming. Restaurants bring much-needed life to the staid air of the preservation zone. And when done well, they can help make these blocks feel like vibrant pieces of our modern city, not simply open-air "living museums" of our past.

The Red Owl Tavern, set into the corner room at Fifth and Chestnut Streets in the new Hotel Monaco, surely has the potential to energize this tourist district with the kind of jolt that Rouge and Parc lent to manicured Rittenhouse Square. Owned by style-minded Kimpton Hotels, it has a look that would appeal to any modern diner.

The dramatic bi-level space is handsomely clad in salvage chic, with wood floors, weathered red barn-plank walls, and industrial lights. Mesh cages cradle big jars of seasonal veggies set to pickle.

Some of the booths and banquettes can seem a bit too tucked away into dark and claustrophobic corners (good luck flagging a server from there). And finding the bathrooms, inconveniently located in the hotel's basement, might require a GPS. But the overall effect is still one of inviting urban energy, with a long bar lining the window wall along 5th Street, where, in warmer weather, sidewalk cafe tables will also bloom. The rooftop cocktail lounge, Stratus, is worth a visit just for the 12th floor views.

The Red Owl's menu of updated American fare could potentially be a draw on its own. And with a caretaker such as Guillermo Tellez, who created Square 1682 in Kimpton's Palomar across town, my expectations were high. It's a shame my meals still seemed hampered by the inconsistencies, both in food and service, indicative of a green staff.

The menu is deliberately more rustic in presentation than Square 1682. But too many details still require fine-tuning. The mussels come in cast-iron crocks that are too shallow, leaving mollusks piled too high and getting cold beneath potato chips, an odd addition that only got soggy in the broth rather than soaking it up. The flavor options were appealing - a creamy Indian curry (as opposed to the usual Thai accent), and a Mexican salsa verde with pulled pork. But neither had the intensity or thickness to really cling to the mussels at all.

Local produce is clearly a priority, which means in winter months, lots of pickles. Unlike better renditions in town, though, the Red Owl's selection - from beets to carrots - are all cured in the same overly sweet brine, which becomes monotonous and dull, especially cut into big, clumsy chunks over the flimsy greens of the "Big Green Salad."

This kitchen's determination to do much of the butchering in-house, however, has paid dividends with a few highlights. The charcuterie platter features a number of excellent nibbles, from hickory-smoked lomo to spot-on country pate. The house-made sausages of the day, which come over grilled toast smeared with white beans, were also worthwhile, from the smoky spice of the andouille to the winey savor of linguica. The seafood sausage had some texture issues, and the ground halibut and scallops were a little chalky without the use of cream, but the flavor was still excellent.

The Red Owl also turns out one of the city's better marrowbones, roasted to gooey warmth and topped with the double-dare of pickled lamb's tongues, which would have been excellent had that brine not (once again) been a shade sweet. I had no flavor issues at all with the Red Owl's burger, an outstandingly juicy 10-ounce patty ground from West Chester beef topped with onion marmalade and spicy chimichurri, good Nueske's bacon, and cheddar. It could actually be the single best reason to come to the Tavern, though I suspect the $17 price tag (bumped up from the hefty $15 I paid) will curb enthusiasm.

Most of the menu is priced in the mid-$20s or less. But value is relative. The service, which already showed signs of poor timing and inexperience ("So, what does that Lost Abbey taste like?" our waiter asked us), is constantly trying to upsell the menu with sides such as cheesy bland potatoes and over-vinegared greens that are just not worth it.

I wasn't surprised our server "highly recommended" the Owl's "Prime Cut" steak - since it was $21 more than any other slice of beef. But I wouldn't go there until this kitchen shows it can cook one of its more modest choices. And these unusual cuts - the tough, pre-sliced Denver steak that was going cold by the time it arrived; or the puny flatiron steak that tasted mostly like its side of Worcestershire-wilted greens - did not inspire confidence.

There were some safe bets on the menu, such as the puff pastry-crowned pot pie made with moist chicken and creamy gravy, just like Tellez used to do at Northbrook Orchards; and the excellent lamb shank over beluga lentils, sauced in tomato gravy tinted exotic with garam masala curry. A basic chicken sandwich at lunch, paired with a spicy-creamy avocado-jalapeño mayo, was simple satisfaction.

But for every success, a careless cooking glitch dimmed another. A beautiful hunk of striped bass atop royal trumpet mushrooms and Japanese eggplant was thoroughly overcooked. Tellez's signature beet pasta, a dish I loved at Square 1682, is rendered too heavy and sticky here, with too much cream on the finish.

The desserts brought a similarly uneven tale, with a mini-pumpkin pie that was overspiced, but a decent bread pudding dropped for a crisp in the deep-fryer. The red velvet whoopie pies were dry. The chocolate-brown butter tart's crust was too thick. But the apple pie? The crust was surprisingly flaky (vodka is the secret ingredient), and the fresh apples inside were roasty perfection in rich caramel. It was a fine American classic to savor from my table with its classic American view.

With a little more polish on the rest of the meal, the Red Owl Tavern could become a destination on its own.

Next Sunday, Craig LaBan reviews Tavro Thirteen in Swedesboro. Contact him at claban@phillynews.com.