I found lot of cryptocurrency exchanges. Still moment Gemini has better options I found. Gemini is a cryptocurrency exchange platform where investors can buy BTC and ETH using US dollars   or just trade between BTC and ETH. It’s a robust tool for more advanced traders, but it’s also has clean, easy to use interface that even a total beginner can quickly get the hang of.
What sets Gemini apart from other exchanges is its embrace of regulation and compliance it’s the first US exchange to be officially licensed for both ether and bitcoin trading. This is an exchange that aligns itself with financial legal institutions, and that legitimacy gives it a certain advantage over other platforms.
It’s not just the appealing visuals of this exchange that cater to high-volume traders, it’s also the prices. Fees range from 0.00% to 0.25%, depending on your 30-day trading volume: heavier traders get the slimmest fees.

@cryptographic, I find much information about Gemini's ID vericgication process via below source.
Now begins a three-step identity verification process:

1. Linking your cell phone number up with your account — this makes receiving login verification codes easy. It’s a pretty standard requirement for a lot of exchanges, as two-factor authentication massively enhances your account security.

2. Linking your bank account using your normal online banking login credentials — just log in using your normal username and password. The bank account must be in the same name as the new Gemini account holder.And don’t worry, your username and password are safe and secure — this step simply makes depositing funds quick and easy. If you don’t want to fork over your login information, you can verify your bank account using a wire transfer instead.

3. Finally, they will ask you to submit documentation that proves your identity and address, like a copy of a bank statement with your address clearly printed.

Source: https://hackernoon.com/a-beginners-guide-to-trading-on-gemini-2c76eda7d58