There is one further important issue about bhava, namely, its relation to jāti, “rebirth”. To my mind, it is here that we find the most important evidence for its meaning.
I am not entirely sure what you mean by this. Do you mean that jāti happens at physical birth, not at conception or at some point in between? In which case bhava could refer to the period in the womb? Or do you mean that bhava refers to the intermediate existence (antarabhava) that occurs after death but prior to rebirth? Or perhaps you mean both? I find either of these suggestions problematic for the following reasons.
I cannot see that the references you provide show that jāti refers to physical birth. On the contrary, an expression such as the “manifestation of the aggregates” must refer to an earlier point in the womb, when a foetus becomes sentient. The same is true of the “acquisition of the sense fields”. It seems to me that jāti must refer to the first arising of consciousness in a foetus.
Further, not all beings go through a period in the womb. In most realms of existence, beings are reborn spontaneously. If bhava meant the period in the womb, these beings would not experience the 10th factor of dependent origination (DO). This seems highly unlikely.
As for bhava referring to an intermediate existence, this too is problematic. The idea of an antarabhava is quite marginal in the suttas, and no doubt this is a major reason why it became so controversial for later generations. It does not make any sense to me that such a minor teaching should be the explanation of an important idea such as bhava, especially in the context of DO.
A further problem is that it is not even clear that all beings go through a period of intermediate existence. It seems possible, for instance, that someone about to be reborn in jhāna realm, enters the jhāna during the dying process, and that the rebirth then happens as a consequence of this. In these cases, there seems to be no room for an antarabhava.
For bhava to have a clear function in dependent origination, it makes much more sense to me to regard it as reflecting a mainstream Buddhist idea such as kamma and rebirth, which is exactly what we find in the definitions at AN3.76 and AN3.77. In this view, bhava is the kamma you produce as a result of your existing in a certain way, with the consequent corresponding rebirth. In fact, on this interpretation, bhava is not really about rebirth at all, since this part of the DO sequence is taken care of by jāti. Still, bhava can be said to imply a particular future rebirth.
What do you think?
It needs to be understood as the āsava (the defilement) of desire for existence. Such shorthands are to be expected in language.