Questions about rock formation

[kvanorsdale]

do I need more rock or not

 

[CodyRVA]

More so personal preference, but I think you have enough. Your aquascape will do well to keep detritus from building from all the flow through those large caves. Just make sure the rockwork is secure to prevent falling. You're probably going to move your rock around a good bit until you're 100% happy, usually takes some time, especially if you start adding coral.