Do you know the strain? A pure indica type would be short and bushy like this. It looks nice and healthy. I did notice the ends of the leaves are doing a rams horn. Are you nuting it? If so, I would lay off them for a while. A rams horn leaf is an indication of too much (N)itrogen. Also, you can always pull the light away a bit more if you are wanting to stretch it a bit. Type of soil? pH level in / out of pot?

GTD