Are ARK ETFs a good place to start investing?

ARK is a good choice, but I wouldn't recommend putting more than 30% of your available investment in the company. In my opinion, the stock price has been too volatile in the last 5-10 years and I don't see any promise of them becoming more stable in the following years. In the last 5 years, they've shown no more than a 40% return, and the stock doesn't even payout dividends. I've also seen their stock price having a 30% drop within 24 hours, and I wouldn't invest in something that volatile.

My advice would be diversifying if you're plan is for the long-term. Splitting your available money into five parts and investing in stable ETFs like S&P500 and/or the Vanguard 500 Index Fund would be a better idea in my opinion.