Quote from: eminan on Today at 10:07:16 PM

What's the best crypto to use for trading on there (least amount of fees, ability to trade for other coins, etc.), BTC, ETH, LTC, TETHER (USDT), USDC?

It all depends on your strategy but most people prefer trading against stable coins as it makes it easier to track your profit and loss in fiat value. Fees are charged in percentage form for all trading pairs, so they are the same.

There are fee discounts if you hold Kucoin shares (KCS) - https://www.kucoin.com/vip/level?lang=en_US

Quote from: eminan on Today at 10:07:16 PM

Since you can't deposit fiat on there and buy coins directly from it (I think?) does that make every crypto to crypto trade a taxable event? I'm assuming there's no way around this? I'm a US citizen.

Check this out, it might help
1. https://support.kucoin.plus/hc/en-us/articles/900002690886-Cryptocurrency-Taxes-FAQ
2. https://www.irs.gov/pub/irs-drop/n-14-21.pdf