Our first attempt to solve this was with a "map of all science" (from 1400-today, 100M+ articles, 1B citations), which we did build but it didn't end up solving the problem that well. We re-approached the problem by pairing a time-based citation visualization, with helpful search tools, and project (or map) state. Our visualization lets you quickly see how search results relate to each other (optionally with nodes sized by citation count). We currently have keyword search, and a network search (called Explore) that scans for highly connected articles up to two degrees away from your map(s) and/or keyword searches. Lastly the project state is nice because as you build up key articles, network search is more targeted, and you can opt into email updates if there are any newly published works that connect to your map as we update our dataset.
It's currently in early access so it's free to use, and you don't need to create an account to get started. You can dive right in and start finding relevant articles to what you are working on or are interested in. Keen to hear feedback on our work so far. Thanks.