It's the loss of an entire ecosystem worth of apps.
No, it's not. With very few exceptions, the Aurora store pulls apps from Google Play. About the only thing I have seen missing from Aurora store is a few super strict banking apps but you can usually just use their web site.
You can do paid apps. You just have to login to Aurora using a Google account instead of anonymously.
This isn't so bad if you use a privacy focused ROM and create a special, single purpose Google login that is only used for app purchases. I also suggest keeping a Google gift card for the occasional purchase.
Privacy invasion doesn't really kick in until you start re-using your Google login and your phone/apps are reporting back to Google on a regular basis with your location, device IMEI, advertising ID, hardware fingerprint, email address, browsing/search history, banking/purchase details (aka Google Pay), etc..
No, it's not. With very few exceptions, the Aurora store pulls apps from Google Play. About the only thing I have seen missing from Aurora store is a few super strict banking apps but you can usually just use their web site.