Whew yeah, that is going to be a potent mix! It's just a matter of personal taste, but I think some people are more sensitive to smoked harmalas than others. That would be way too much for me.

I also love to add white sage and also green sage (Salvia officinalis) to my changas. They absorb stuff really well. Especially good for strong mixes like yours.

Also another matter of personal taste but I LOVE damiana in my mixes. I roll cigarettes of the stuff and smoke them sometimes. Yummy.

The best way, I find, is to put some of your favorite herb on top of your changa to protect it from the flame. The sandwich method, basically, but most of the time I don't bother to put any herb in the bottom of the bowl, just the top to protect it from the flame. So even if you completely cherry the top herbs the spice will most likely vaporize before it has a chance to burn.

You do have a very heavy blend though. Might take several draws to vape all that spice off!