Firstly, thanks for the kind words, Jeff! We do put in far more time and effort than may be apparent on the surface, and not everyone is appreciative.
I've discussed your suggestion with the other moderators. It's a nice idea in principle, but unfortunately we don't think it would be practical to implement. For one thing, there is no one system of grading (and the Delcamp system refers specifically to those scores in the Delcamp collection). And, as you say, judgement of the level of a piece can indeed be pretty subjective, and complicated further perhaps when it's for more than one player and the parts may not be equally difficult. The likelihood of a number of different members allocating a similar grade to a piece of a similar level is probably slim, and that would just open the door to distracting discussions about grading. We're wary that it might even discourage members from posting their pieces here if we put an extra hurdle in their way by asking them to decide on a grade.
Posters occasionally mention within the text of their posts, or in replies, whether a piece is suitable for beginners, and in those cases you could find the relevant topics using the advanced search tool here
, entering an appropriate keyword in the first field, such as "easy", scrolling down to and clicking on the "Virtual duos, trios and ensembles" forum in the Search Options, and then on Submit. The keywords "beginner" and "beginners" (both indexed separately) also bring up a few results. I understand that you're looking for something a bit more challenging, but just mention that in passing for anyone looking for easier pieces.
So I'm sorry we can't take up the suggestion, which was nevertheless worth raising and considering. You'll probably find that you'll eventually become proficient anyway at looking at a score and knowing instinctively if it fits your skill level, and the more you try, the sooner that will come.
Classical Guitar Forum.
"Experience is something you don't get until just after you need it." - Steven Wright