Excellent Yoganewgirl, you obviously are taking your Yoga very seriously. It is refreshing to see a serious spiritual aspirant on this forum.
I have also been neglecting the physical side of Yoga for a long time. Although I have done asana Yoga on and off throughout the years, it has never really drawn me, in the same way the mental aspects of meditation, pranayama and spiritual study(Jnana) have. Now, I realize that physical health is equally as important, and by removing the tensions from the body through the asanas it will lead to a better flow of energy in the body and facilitate meditation.
I must say I am not really drawn to any of the vinyasa stuff like Surya Namaskars etc. I would rather do the asanas in the traditional Hatha Yoga way, by holding them for a very long time, and then moving onto the next asana. In this way the asana becomes more of a meditation. Iyengar Yoga is probably more closer to what I want.
Kundalini Yoga, as in the the 3HO type is dubious to me. I tried it a few times, and it seems more like Yoga aerobics than genuine Yoga. I am not surprised about the hyperventilation you described, I experienced that myself and many others I know experienced similar symptoms, light-headedness and nausea. Hyperventilation is not a good thing and Yoga is not suppose to induce it.
Deep breathing before meditation is a great idea. It is always advisable to start any meditation with a short round of pranayama. The pranayama harmonizes the breath and calms the mind, introverting(pratyhara) the senses and preparing it for dharana - assuming the object of meditation. It also helps to begin the meditation by saying your affirmation “I am the witness” to put yourself in the witnessing mode.
Systematic meditation where one begins with the body, then gradually moves to the breath and then the thoughts and feelings is an effective meditation. It mimics the actual process of meditation where by one begins with a gross feeling of body, then gradually consciousnsness becomes more and more subtle.
I can certainly see the sense in not eat too much per meal. I just end up feeling really heavy and bloated if I eat too much in a meal. I have a weird metabolism. If I eat too little I just end up looking pretty skinny(but not underweight) but if I eat to gain weight, I gain it in the worst area to gain it: stomach lol My aim, as shallow as it may sound, is to gain enough weight to look at least decent, but be toned at the same time. In order to achieive this I am going to have to eat a bit, because I have a really fast metabolism.
My decision to eat meat again, is motivated by the need to gain weight, because meat contains more calories and protein, otherwise I also think a vegetarian diet is more Yogic.
You should consider as part of your routine concentration exercises i.e., Yoga Trataka. These are great exercises to strengthen your powers of concentration, and will aid your meditation.
In order to select the best techniques to include in your plan I highly recommend the Bihar School of Yoga books.