I'm pretty sure you can reach theta with deep relaxation, which is what I was doing last night, my body was very relaxed for a long time but I couldn't fall asleep mentally, probably because of the silly mp3 I made, so it's likely I got to theta and OBE'd because my body was asleep but my mind awake.

Yeah, a friend of mine told me about his friend who was able to do that, she could carry out tasks around the house while astral projecting, pretty fascinating stuff, I imagine you must be a super expert in order to do that though.

Sure, make one if you want, writing down what you're doing to increase your chances of LDing can boost your confidence and motivation.
I don't think you were making a 'huge' mistake by trying SSILD and MILD, you can keep doing it if you want, what's important is to increase your awareness like you said you want to, in order to get lucid more naturally and frequently via DILD. WILD is great for an on-demand LD, but as you saw, it's tricky to get for most people. But anyway you're welcome, glad I could help, and good luck to you too~