Under 2k for a closed burner, 30" gas range in stainless is easy. GE Profile, Bosch . . . there are various offerings that should work well.

As to adequate ventilation . . . well, there's what it takes to capture smoke, grease, and other by-products of cooking; what it takes to clear the room of odors and/or to manage heat; and there's the question of what bothers you. For smokey cooking of the type you described, I'd guess that 300 cfm is well on the low side. You might be fine with it, but it's not going to clear the kitchen. Really, it shouldn't cost you much more to get a 600 cfm blower.

As you are figuring costs, be sure to account for the installation of whatever sort of ventilation system you are going to adopt. That's not just hanging the unit, but installation of the ductwork -- everything between the hood and the outside.

One big difference between slide-in and freestanding is the control location. AFAIK slide-in always has controls in the front, freestanding puts them on a back panel.

I would take a serious look at the new kitchen aid. It looks awesome, and the price point isn't far above your budget (might even be able to talk lowes down to 2k if you reference Plesser.com's price). Plus, you can get a 5 year warranty through lowes.. which is pretty huge.