Hmmmm ... I can't think of any tool I use specifically because most of the issue I find with projectors is clipping. This concept is something print designers may be more familiar with than web folks but in the print world, you can pretty much guarantee that anything below 5% ink isn't going to print consistently (obviously some print-makers can be more accurate).

In the world of screens, you'll see clipping happen more dramatically. For example, try a color like #fdfdfd on some LEDs and it'll likely be blown out. Projectors tend to clip on both the light and dark ends of the spectrum by a range of 10-15%. The best way to design for this is to use the HSB sliders in Sketch to ensure nothing is in those ranges that you wouldn't be okay with coming out literally black or white in a presentation. You can also look at RGB and see if any color comes in above about 240 or below about 40.

If the meta question here is "how much should a design tool provide safety features against a lack of design expertise," I have mixed feelings.

As a designer, I think the thing people hire us for is both our knowledge and skill. Most often the best clients I've had are the ones that have taken the time to try to design or implement things themselves. By doing so, they've had an opportunity to understand some of the mechanics of design and how much skill it truly takes to be a good designer.

However, design (at least in the UX/Web space) has become more democratized. Anyone can read something like the Sprint book and begin to implement its practices on their own. In effect, everyone has become a junior-level designer. To help newcomers bridge the knowledge gap it may be necessary to have some tools that have guardrails to prevent disastrous mistakes.

Going outside of Sketch and learning just enough code to build your own prototypes is the best solution I've come across for these scenarios. There are some apps for prototyping that could handle stateful components better than Sketch, like Axure, but everything you're looking at is going to have trade-offs. Even if you're not quite ready to code your own stuff yet, something like Webflow could do the heavy lifting for you while you focus on the design. Either way, Sketch is limiting and you'll probably keep bumping up against its edges for complex/stateful prototypes.

Not utterly useless but I generally don't ask for preferences in feedback. I'm typically looking to understand the "why" behind feedback, e.g. what is the problem this piece of feedback is trying to solve.

I wouldn't use it for design feedback but I could see it being used for more simple design questions, e.g. for a UI selector pattern "which of these UI patterns is the selection clearer?"