First of all, I suggest looking into other teks. if you're going for an STB, I think noman's tek is more appropriate.
As for other plants, yeah you can in theory extract dmt from some of them, but its not easy to find a plant with such a consistent high yield and low impurity profile. With phalaris, I would suggest looking into strains that have been analysed with good amount of dmt and low of gramine (for example AQ-1). Finding wild phalaris with really good alkaloid content is probably much more unlikely.
Also check this file for info on phalaris analysis and growth/stress conditions to maximize alkaloid content:
https://www.dmt-nexus.me...rum/resource.ashx?a=8255Maybe doing multiple recrystallizations with aliphatic naphtha/heptane/hexane on phalaris extracted stuff is a good idea to try to eliminate gramine content, since according to Merck Index, it should be insoluble in it. Soon we hope there should be some more tests regarding gramine solubility.
As for psychotria viridis, it might be more oily and lower yielding, also with the chlorophyl. P. viridis alkaloid content is also much more varied than the consistent 1+% of MHRB, but its certainly possible to find some that is good yielding, when certain steps are followed.
Some years ago people would suggest extensive defatting, but nowadays the trick is to use fumaric acid and precipitate the fumarate alkaloids out of a solvent (FASI on limonene or FASA on xylene for example). Then convert the fumarates to freebase in one of the manners, such as described in BLAB tek / wiki.
Be sure to let us know the results if you do try from something else! Good luck!