first, 倒挺 is NOT a word. 挺 means "very" so 挺 = 很 or 非常 for example, 挺好 = 很好 or 非常好 中餐挺好吃 = 中餐很好吃 = 中餐非常好吃 = chinese food is very delicious 倒 here means 倒是 so for ur example, 這點 倒 挺符合人性的呢 = 這點 倒是 挺符合人性的呢 倒是 is always put before verb when do we use this word? when u want to express "出乎意料" ----- in other words, something shocks u or surprises u. for example, in ur phrase "這點倒挺符合人性的呢" it means that u never find that "這點 是 符合人性的" before. u see at the end of the phrase it is 呢 here 呢 is used to highlight the tone and the manner of speaking. so ...倒(是).....呢 means: wow I never find this before.(出乎我的意料)

倒挺 is not a word itself. 挺 is an adverb meaning "very, quite", like 挺不错 = quite good, 挺符合 quite fits/maches. 倒 itself means "reverse, backwards", but here it means: 1. the thing you are describing is kind of beyond your original exception, but not too much, which means it's still logical and makes sense for you. 2. there are several characters of a thing that you are describing. its many characters are similar (all small, short, long, good, bad, nice looking, etc.) but several others are just the opposite. 3. you use it to express approval. sometimes all the above 3 meanings are included in a sentence. for example, a man's girl friend are so unreasonable and he dislike her more everyday. but she has a very obvious virtue: being kind and caring to old people, especially to her and her boyfriend's parents. so his friend can say: 她这人很不讲理，但对老人倒挺好。= she's very unreasonable, but she's quite kind to old people (our parents).

這兩個字都是 副詞 用以修飾 符合 倒： 反而。表示出乎意料之外。 「大風大浪都見識過了，這會兒你怎麼倒沒主意了。」 挺：很、甚。有強調意味。 如：「他人緣挺好。」、「她待人挺和氣。」、「她看起來挺高興的樣子。」 "這點倒挺符合人性的呢" 以前我從來沒想過 這點是符合人性的 而現在知道了 這點不但符合人性 而且是非常符合人性的 這令我有點驚訝了

it's 这 点 倒 = this point relates to and 挺 符合 = very suitable

"That's kind of humanity."