I hear ya...but even in low light, I can ding the gong every bit as well with my Nikon as you can with your Swarovski if all else is equal. I think my brightest / best light gathering scope with an amazing depth of field is a Sightron I have about 200 bucks or so invested in. A good eye relief that I'm comfortable with and that can vary a bit is what I look for. Burris scopes kill me in that regard. I have to have an exact cheekweld sweet spot to use any Burris I've ever had or still have...kinda screws the pooch when you sight one in on a bench and then try to lean funny around a tree or lean forward to get a shot off. I think every time I have ever "scoped" an eyebrow was with a dang Burris...nice scopes though, just persnickity
If we're splitting hairs, no scope gathers light. It's all about the ability for the lenses to allow light to pass through and to the eye. That's where the coatings, and particulate free glass comes in. Higher end scopes have higher end glass. Glass is graded just like diamonds, and you do get more clarity for the money. You may be able to clang the gong as well as I can, but I'll be able to see it for 5-10 minutes longer than you will.