We used PC to track our investments across multiple platforms before Schwab introduced features to connect everything to our brokerage account. Then we deleted our PC account.
I would not use PC to invest. Their fees are lower than most individual financial advisors, but we still believe in doing that ourselves. Most advisors only beat the market by luck. Research it: more than 90% don't beat the market over time. If you haven't yet researched how the fees for submarket performance add years and even decades to your FIRE horizon, please do.
Instead, just pick index funds and an asset allocation that work for you, and rebalance periodically. It's daunting at first but soon it's like riding a bike. We use Ray Dalio's All Season's (aka All Weather) Portfolio. It's a low volatility portfolio that fits our situation and goals. Give it a Google or message me for more info.
Many others here just use a single Vanguard or other low-fee broad market equity index fund.