Visa granted after prior refusal - my experience

I applied on behalf of my partner who is Ghanaian, I am British, we live together in China. We applied for Standard Visitor visa so travel with me to the UK in the summer. Prior to this, we also secured Schengen visa for him, which in hindsight, was much easier! Here is our experience in case it helps anyone:

Context: My partner is a full-time student, with irregular financial support from family (in addition, this comes from WeChat so it's hard to verify). I have a full time job. We live together, and have strong travel history, but this was his first time applying to the UK/Europe. For both Schengen and UK application, I was acting as his sponsor, hoping it would put us in a better position. For UK visa, this turned up having little impact.

First application: biometrics on 22/04, refusal came on 30/04. Refusal cited two problems, one of which was an administrative error (I made a separate post about this), the other problem was his visa in country of residence was expiring two months after his scheduled departure from the UK.

Second application: I decided to overprepare this time. Someone on reddit recommended reading the ECO guidebook to really understand what they're looking for, and this was immensely helpful.

1. We obvs addressed their original concerns: his student residency permit was renewed for another year (this is not a standard procedure here but his professor put a word in for him),

2. I created a separate financial document detailing all larger transactions in his accounts, color coded them into categories (allowance from family, transfers between own accounts, etc, to prevent someone misreading his statements again), and added up total income per month. I then averaged this to get the annual figure they ask about on the application (in the first application, we just give a rough estimate that was turned out to be significantly lower than reality).

3. To strengthen his ties to country of residence, we also extended out apartment lease for another year. ECOs operate on the balance of probability - you have to convince them that the likelihood of you leaving the UK at the end of your stay is greater than the likelihood of you overstaying.

His second application biometrics was on 18/05, visa was finally granted on 01/06. I'd like to add that having to deal with VFS website was the thing that nearly broke me in the end. But we did it!