After a discussion with one member of this forum, I recently switched from exclusive focus on the breath as sensed within the nostrils to a more holistic focus on the inner sensation of my body, including the breath. I start by intently focusing on my breath at the nostril and then expand to include my body, including the breath. I focus on how my body feels on the inside (so the feeling is kind of 'shaped' like my body). Eventually, I start to feel as if my body is breathing and I focus on this as well. When I inhale, I feel a slight bodily expansion, and when I exhale a contraction occurs.
This practice has been very fruitful for me. Like the OP, I feel much more open, aware, concentrated, and mindful. I can sit for longer periods of time, because I become concentrated and time seems to go by more quickly. Additionally, I become concentrated much earlier in my session. I have moments (during and after each session) where sense-based actions feel somewhat depersonalized. I also have a variety of sensations I'd like to run across some of the more experienced samatha practitioners in this discussion. I feel subtle tingling sensations within my body (especially my face). Certain parts of my body seem to lose sensation or 'disappear' as sensory experiences, and this is especially so within my face and hands. Like other meditators, I have a forehead sensation although the way I would describe it seems somewhat different from other descriptions that I have seen. For me, the sensation is a kind of tingling. It feels cool (temperature-wise). It arises and persists for a while, and then falls if I change my focus (away from the holistic breath-body feeling). Sometimes, the sensation arises or persists outside of meditation by my merely focusing on the spot where it normally occurs or by paying attention to my breath.
I tend to associate this breath-body awareness, as described by the OP/other posters and myself, with the "breathing in sensitive to the body/calming bodily fabrications" aspect of the Anapanasati Sutta method. It seems to me, based on what I have been experiencing recently and on what others have to say, that the sutta's method is less consecutive and layered (focus on this, then switch
focus to another object) and more a process of subsuming. So, I think of this method as less about 'not observing the breath' and more about observing that the breath (as a sensory process) is more than just a stream of air. I think of nesting dolls. You have one sensation which contains or enters in to another sensation, all of which are part of one process culminating in complete, unhindered, undifferentiated awareness of body and breath (the large outer doll). Hopefully, I'll get to the outer doll in time.
I do not want my house to be walled in on sides and my windows to be stuffed. I want the cultures of all the lands to be blown about my house as freely as possible. But I refuse to be blown off my feet by any.- Gandhi
With persistence aroused for the highest goal's attainment, with mind unsmeared, not lazy in action, firm in effort, with steadfastness & strength arisen, wander alone like a rhinoceros.
Not neglecting seclusion, absorption, constantly living the Dhamma in line with the Dhamma, comprehending the danger in states of becoming, wander alone like a rhinoceros.- Snp. 1.3