Yes without a shadow of a doubt. These are the most important metrics to look at in fact. It will be helpful as well to identify a (one) core super metric unique to your business as an overal measure.

E.g. Blogger - Number of blog posts per day Flickr - Number of photos uploaded per day

After that once you start breaking down into AARRR, you can start defining more mini metrics to watch and optimise at each stage of the process.

Be careful with data overload. Less is more. Is finding out the number of users with a personalised profile picture meaningful to your business RIGHT NOW? If not, shove it and move on to the next metric.

Less is more!!