grammaticality - Grammatically correct questions in a survey

1: What tools do you use for recruitment? (You left out use)

2: What are your favorite features of these tools? (your, not you)

3: What functionalities missing in these tools do you wish you had?

You could rewrite 2 and 3 as:

2. What do you like best about these tools?




3. What features would you like to see added to these tools?

My rewrites of 2 and 3 are simpler, but you have to judge your audience; your audience might respond better to words like feature and functionality.

As to how to formulate your question: you were very polite!