Time + weight isn't enough info.
What temp is your water?
In general you can usually decrease one and increase the others, or visa versa and hit the same ballpark.
I'm still struggling to figure this gong fu thing out so what may be obvious to you may not be obvious to me and/or I could be totally off base here, but here it goes anyway....
Finding the tea for me is really moving those three parameters around till I find the right combo. Keeping one or two constant helps find an acceptable brew quickly but to really find the sweet spot you need to vary all of them IMO. Some teas like to be packed, others like room. Some like boiling water, others don't. etc.
Longer brew times seem to bring out more complexity, so I usually start there, ie if the tea is too simple lower the temperature or reduce the leaves and extend the brew time. With shorter brew times the complexity comes out in changes between brews it seems which can be fun too. Finding a way to get a stronger tea is usually getting the right amount of leave in the container, too much and you can't brew long enough before it turns bitter, too little and you can't get enough flavor before astringency shows up.