Proprietary models. I know most people are used to gpts but also try Gemini models and mistral proprietary models

Cheaper price per token than openai gpts

Performance you'll have to try that using your own approaches and see what's better

Don't limit yourself to openai models alone but also openai models are also doing so well too .

I guess I'm doing well because I started the competition early

Time is directly proportional to your performance in the leaderboards In most cases