If you're using ChatGPT Plus only for GPT-4, you can get it cheaper via the API. I use it quite a bit - doing PRs, writing code, stories, hackathons, asking step by step instructions on how to do things. It cost me $3 last month.

You can use the OpenAI playground, build your own chat interface, ask GPT to build it for you, but I just use Chatblade: https://github.com/npiv/chatblade