Based on your personal experience and/or scientific data. I have only experienced peganum harmala twice. Once in brew and once powdered in capsules. No visuals, only a feeling of lightness in my body is what I remember. Dose in brew was 2-3g and dose in capsules was 2g.

Both Rue and Caapi, and Harmala extracts are pretty safe on the body, some seem to think Rue feels toxic but it's not toxic, i've worked extensively with Rue, i like it, and can clean up it's bodyload/headspace with Lemon Balm or some other admixture plant so it works just fine for me. As for physically safest, i would say probably Moclobemide even though it's a pharmaceutical, it's simply a reversible MAO-A inhibitor and doesn't have the other effects that Harmalas have, so while they're are pretty safe, i would say Moclobemide is probably the safest and with the least side-effects.