It can take a while. It took weeks for my betta to decide to start using his temple. Then when I totally redid the tank and moved the temple to the middle of it (it used to be on the right) it again took him another few weeks.
Very cool in the future I would like to try my hand at a sorority (when I get the appropriate sozed tank that is) but ot also seems kind of scary so idk.
Definitely looks male to me at this point as well. He is growing very nicely and has some really great looking color coming in. You are doing a great job taking care of him so keep up the good work.
Tried to get a pic of him flaring. All I have is this really big mirror which I balanced on my desk on the front part of my tank so I was at a really weird angle). The beard is bright red like the fins. (sorry for quality)