Ok first regarding rue, extracting is so easy, I definitely recommend it. I've never had these bought extracts, dont know how much the "10x" actually means 10x concentration of alkaloids or just 10x in terms of weight but maybe the extraction technique isnt so efficient and therefore the ratio of impurities:alkaloids will change. One possibility would be (if you can afford it), to first consume just the extract. Find your dosage where you feel some distinct effects from harmalas (light-headedness, etc) but not so much that they are too strong and you lose balance and can barely walk. Then when you find the dosage, next time add dmt with this dosage. You can make your smoking method (vaporgenie?) ready with some dmt in case you dont get where you want the first time, then you vaporize on top of pharma and it will definitely be very potentiated.
Regarding dmt dosage, thats way too strong for your first time. There is a huge variation with metabolism regarding oral dmt use. There are people for whom 50mg oral dmt would totally kick their asses, and for others they would need 200mg. You cant know beforehand, so better start low, dont start with more than 50mg for the first time.
I've read people saying freebase is more poorly/slowly absorbed, I took it once as freebase and it worked fine for me but it was very harsh on the stomach. Also if you extracted with petrochems, I suggest strongly that you redissolve your freebase in non-denatured ethanol or pure acetone and re-evap, to get rid of these solvent traces. Trust me when I say that naphtha burps are not fun. In any case I definitely suggest either dissolving it in juice (the most effective way.. do note that dmt kinda refuses to disslve in juice, you have to heat it up a bit and mix very well, but at least try to get most to dissolve), or put it in capsules (and poke a hole in the capsule), but that is much less effective, in my experience effects are diminished by at least a third, compared to juice-dissolving, though advantage is none of the horrible taste and nausea is diminished too. If you put in capsules as freebase, its still harsh in the stomach at least for me, so I would rather recommend if you can, to turn it into a salt form like fumarates.
good luck and let us know how it went!