Having different lighting in different parts of the cage is great IMO - gives them a chance to regulate - I just got an extra wide cage for my panther and I've been amazed by how much of the cage he uses - I would suggest a couple of vines or branches going across - at different levels - you can use the vines to thin out some of the other stuff if you think your getting too much shade- just by giving the plants something to hang on to.
It gets way colder than 70 in the wild- heat lamps aren't good - a drop at night is .. as long as you have a basking area- keeping females at a bit lower temps is something some do to lower egg production -