Grammar problem

句式上的文法
sentence structure大致正確
但style和用詞則可以斟酌一下

前句用is(present tense)來把better定位為一種真理，
那麼後句的內容時式/動詞get相對地便是表達無乜變數的真理才算是好的condition/結論，否則給人以片蓋全的論據。另外主角你用了people(人/人類/人群)跟building的關係其實可以更specific(使用大廈的人/用戶/住戶...)

所以只改修辭用字我會寫
The better the building design is, the more comfortable the occupants get.
如果連理據都改埋我會寫
The better the building design is, the more satisfied the occupants get.

你可以用反證法去考驗你的句子的：
If ask yourself/anyone: Can you say I am comfortable(or satisfied) in a building equals the building is better designed?
那一個用詞會令你更肯定必定是一個better design.當然還可以有很字/詞選的，是觀角度加上你想比對的design所代表範疇是甚麼，重點是這個字如果可以涵蓋更廣和更全部人會肯定才算是好的評論或議論句/文。

The better design a building has, the more comfort people get.
The better the building design is, the more comfortable the people are.

The better the building designs, the more comfortable the people get.

design 之後 Is 很奇怪, 不能這樣用