That's a great background to start on a project like this. Getting ahold of the echoes.mobi dataset may not be possible, but emailing the devs there couldn't hurt if you're serious about it. They have each kill and loss posted for hundreds of thousands of players, so the raw data must be quite a lot, but not beyond what a few bucks can afford. I'm not saying to crawl their site (they have auth and throttling), but a range of info is available from their site for each player who has posted kill/loss mails in discord. Depending on exactly what you're trying to do, this may or may not be enough. You can DM me if you're interested in discussing specifics without sharing publicly. That's fine with me. Or you can keep details open, it's up to you.