Practically the only thing I look for in a description of a build, is to see if MOO is used, and that I need to enable it before placing the lot (instant skip if that's the case). I only search for hashtags if I want a build for a spesific lot, for example one of the Sulani beach properties or San Myshuno penthouse.
For my own builds, I will use #nomoo and #nocc. Also for any special rooms I've made, like sunroom, library, laundry, greenhouse etc., which I don't have in every home I upload. For the general description, I'll list how many bedrooms/baths, if it has a separate dining and living area etc. I'm not really good with descriptions, or using hashtags. Mine are more practical info than anything.
As for making your uploads more eyecatching, I don't really know. What catches my eyes is a nicely done outside area, since that's something I don't find as fun to do. As for sims, I don't download those very often. And I usually skip those with custom poses. Not because I don't like them (I dislike most of the games poses too, especially for my boys), but because they are often for generic cute/hot sims, and I just think they all look very similar, rarely any unique and interesting sims.