You can self host something like https://big-agi.com/ and grab your own keys from various providers. You end up with the above, but without the pitfalls you mentioned.
BIG-AI does look cool, and supports a different use case. ABACUS.AI takes your $10/month and gives you credits that go towards their costs of using OpenAI, Anthropic, Gemini, etc. Use of smaller open models use very few credits.
The also support an application development framework that looks interesting but I have never used it.
