I do agree this would be a nice feature, but it presents all kinds of technical challenges we need to address. We've made some changes to the site to offset it, but querying mods for users with a tonne of blocked tags/authors is an incredibly heavy request. Allowing individual mods to be blocked would make the request more specific and increase the time it takes to process. We can move the filter controls to the "front end" meaning that the search will load all results and your browser will figure out which items to actually show, but this would prevent mod results from being properly paginated - so you'd ask for the "first 20 mods for New Vegas" and after filters that page may have 12 mods on it, moving to page 2 you may have 3 results, etc. In short, it's something that would be super cool, but to do it well at the scale of this site requires significant planning.