Family/Spouse visa advice - British citizen engaged to non-UK partner

Hi all, I’m a British citizen and my partner is from Pakistan. He’s currently on a post-study work visa that is due to expire in January 2026. We are engaged to be married and trying to work out the best visa route for him to stay in the UK legally.

Some key details:

I work part-time and my annual income is below the £18,600 requirement. I am looking for full time but at the moment I can only go on what I earn right now. I receive a small amount on universal credit, this still doesn't take me over the required amount.

My partner is on a zero-hours contract but works 37+ hours a week.

We don’t have significant savings.

My main questions are:

1. For the spouse visa, does only my income as the sponsor count, or can his income also be included since he’s working full time?

2. Would it be better/safer to apply from inside the UK or from Pakistan once married?

3. Are there any alternative routes we should be considering?