My only issue with unDraw (and Unsplash) is that the license isn't conclusively a free software license due to the "don't scrape our site and run a competing service" clause(s). I'd be more comfortable with it if they more clearly separated the license into one for the assets themselves (preferably something like CC0 or an ISC-like license) v. one for the site itself (which would be the right place for a "no scraping" rule).
The impact's minimal, but it still rubs me a smidge wrongly.
Would love to have an online tool for this also, as others have said.
The style of work really reminds me of undraw [1]
[1] https://undraw.co