Basement Insulation Question

I had my basement finished about 4 years ago. At that point I elected to use Roxul mineral wool insulation over fiberglass due to its superior ability to resist mold/water etc.

Overall I was very happy with the job that was done, but notice that the basement is still quite chilly relative to the main floor, which makes it uncomfortable in the summer. I've closed the air registers to the basement to limit the AC from blowing more cold air. The contractor installed a sub-floor etc as well.

At the time that we did the reno I would say that spray foam insulation wasn't something that was perhaps as main stream as it is now, and frankly, I regret not choosing it, as a neighbour of mine used it when he finished his basement and it is noticeably warmer than our basement.

Other than using an electric heater etc, do any of you have any suggestions on how we could warm up the space? I was thinking that radiant floor heating may be an option (don't mind taking the floor covering up at some point as we used laminate).

Thanks in advance....Ian