Personally, I just look at what I own.
Mostly my country code .ca then .com's with a few .net, .org, .app sprinkled in.
However I managed to my first .xyz to actual use on our marketplace, that's the first extension outside .ca and .com for us to achieve this for me.
Other than that I own one more targeted .xyz and in most cases I buy those only with a possible end user in mind.
More and more now I tell domainers go ahead and register if you can think of 1-3 possible end users. If you cannot think of at least one then chances are you will be renewing for a long time.
Almost all new TLD's will sell almost 85% in the one word category, 10% in the two word category and about 5% in 3 words and above. I am probably being generous with the last two percentages but it really hurts me when I see domainers registering two and 3 words in ANY new TLD.