See those rocks above the xenia patch? Well, might as well start imagining how they look covered with xenia too. I always recommend placing the xenia high in the tank since it will grow towards the light - quickly, and take over almost everything in its path.
And you've got that elongata variety. Weed is an understatement IMO. Pom pom grows a bit slower and is prettier I think. I do also believe it's time for you to start propogating and thinning. I got small pcs of rock and affixed xenia to it. After it attached, my lfs gave me $8 per for them. They'd fly out of the store. I'll see if I can dig up my old "tutorial" thread on it somehow and post it again here.