Just call Coinbase for help... oh wait, I forgot that they play a "we have no one to help you" message and hang up without even offering you the option to leave a message.   

So then just email them... oh wait, I forgot that they don't respond to emails.

So then just pray.

Is there an exchange (or platform) that meets the below criteria?

1) Reputable company in reputable country, preferably USA.
2) Has a phone number where a human will answer (unlike Coinbase) and/or will reply to online support in a timely manner.
3) Good for high volume.
4) Low fees for high volume.  I regard even 0.25% as high.  If you buy, say, $1m in stock, you'd pay $10.  0.25% is $2,500 for a transaction fee.  I understand the fees won't be the same as a Charles Schwab, but how low can one go for high-volume purchase of digital currency such as BTC?
5) Can fund with USD.
6) Can transfer out ALL of one's USD or BTC etc. in one day and not be subject to stupid daily export limits on one's own assets.

It seems to me that there is no decent, low-cost, trustworthy option for the larger players.  I hope I'm wrong.