I'm sure the V6 is a great scope. The NF and Leupold scopes are also nice, but for this application I'd go with something different.
The large range magnification scopes are heavier than scopes with smaller range (like 4-16x instead of 2.5-15x for example). With poor light conditions, ranges are short, and the OP stated he usually just holds over without using target turrets or reticle subtensions (unless I misunderstood). No need for target turrets. All the availible money can be spent on optical quality.
I'd go with a European scope with a minimum objective size of 56 mm and a magnification of 2.5-10x , 3-12x or maybe 4-16x. Target turrets and large magnification are unnecessary features, and big magnification range adds weight which could be downright detrimental.
I recently bought a Kahles k624 for use in low light hunting. It's great! Very bright and clear glass. When hunting I only use it at 6- 12x. I would have been better served with a fixed power 8x scope (check out Karl Kaps or Schmidt und Bender classic scopes), but then I'd have to get another scope for target shooting and I did not want that.
A very good low light hunting scope is the Zeiss Victory HT. I believe it's availible in 3-12x 56 mm. The glass is supposed to be absolutely top class (I admit, I've never used one) and 12x is plenty for most hunting applications. The 3x low magnification should be very useful when moving around.
There are also a bunch of S&B scopes that fit the bill, including the 4-16x 56 mm PM2 Ultra Bright (which has all the long range features you could ask for) .I wanted to get that one instead of the K624 but it was a lot more expensive so I sacrificed the extra FOV. If you don't care about FoV and you REALLY want to prioritize weight and low light performance then consider a fixed power 8x 56mm scope. Fewer lenses means lower weight and less loss of light.