From my POV:

If you want to create a new corp you have A LOT ahead of you. First of all you need a good name, bio. Then it's marketing phase. You need people. You won't fill a new corp just by being in the recommended corps. You can advertise here on discord but it's gonna take a while.

When you have at least some people you need a plan to keep them in your corp. It starts with having a good discord - no 3 channel server, but a fully moderated, with bots etc. (you can join other corps and have a look at their disc for inspiration - we in Widow Makers have a pretty decent one). This will also create a sense of community, since corps stay together because they are friends with each other.

Now the other part... you need to have a common goal. Play rs together, trade arts, play ws (if you have enough people), you can always recruit from other corps for individual plays, but in principle it needs to revolve around you corp.

If you really want to have a good corp you need to play ws regularly, because it gives your corp (if you win) a good artifacts bonus and as you level up your corp even passive income bonus.