That's some really interesting idea. But what if it will make too many "false positives"? Maybe too many word pairs will be considered more related that one could expect.
I don't really remember how i've come with that idea :) Basically i've become obsessed with word games lately and made couple of them. I'm most proud and happy of those two:
As for Enlinko, it's hard game to balance. That's why i've made three difficulty levels. As for daily puzzles, i'm now using semi automated generator - it generates lot of pairs, try to solve them, check if solution counts match some rules and then i'm hand picking those potential pairs for daily puzzles.
I guess data used for making those vectors doesn't contain many occurrences of those two words in relation.
Anyway, that's downside of word vectors idea. There always will be some words which we human will consider more or less related than word vectors.
I've tried finding best one. It's different what Semantle uses (word2vec from Google) and different what Contexto uses (Glove). But still there are probably many word pairs which could match better.