The NV was Ruger's response to demand from cowboy action shooters and a Blackhawk might be better suited to your intended uses, i.e., targets at the range and plinking in the field.
Sights. The fixed sights of the Vaquero and New Vaquero look nice, but they're harder to use than the adjustable sights of a Blackhawk. Adjustable sights lend themselves to shooting a wider range of ammo because you can elevate them when using heavier bullets. In sunlight, the glare from the front sight of the stainless Vaqueros and New Vaqueros can be a problem, particularly for aging eyes. I eventually had adjustable sights installed on my original Vaquero.
Frame Size. The biggest advantage of the New Vaquero is its smaller frame, which makes it marginally more comfortable to pack. Unlike the original Vaquero, the New Vaquero is not strong enough to handle the "Ruger only" .45 Colt loads, but that shouldn't make a difference at the range or for plinking or if you want one in .357.
Finish. The faux color case hardening on both old and New Vaqueros is reputed to wear off easily. That's not of course a problem with the stainless steel versions, but the tradeoff is the aforementioned glare from shiny front sights.
Loading ease. The reverse indexing pawl on the New Vaquero makes loading a little easier, but feels kinda clunky to me. Aftermarket free spin pawls are available for both Blackhawks and New Vaqueros, however.
In sum, I think the New Vaquero would work for your intended uses, but a Blackhawk would likely work better. A viable compromise might be the .357 50 Year Flattop Ruger made in 2005. It has the smaller frame and reverse indexing pawl of the New Vaquero, but also has adjustable sights and regular bluing. There are still some available if you shop around some.
You'll love it. Smaller, and not quite as strong as the original, but it will still last for generations. The Rugers are the favorite with Cowboy Action Shooters because of their price and reliability.