variations of sexual mores

I doubt it matters much but this seems like the relative moral equivalencies of sexual acts. I'm not sure why I bother, but it amuses me to consider moral and ethical boundaries from time to time and to describe them in gory detail.

Assume that pretty much every one of these is "a physical erotic action undertaken by..."
1) persons expressing a consensual and equal moral, physical, and emotional bonding of intimacy through that act. Issues of consent weigh heavily upon the likelihood that this action is morally acceptable, such that it is unlikely to find actions between persons of adulthood both in physical age and maturity and persons of immaturity, both in physical or mental age as morally acceptable. On occasion such morally permissible or impermissible actions will be legal or illegal because it is impossible for the state to assume that persons above or below arbitrary ages have appropriately developed their emotional state to accommodate such physical activities as expressions of intimate feeling. I can make no assumptions that the persons involved are legally bonded to one another, nor bonded by sanctioned rituals, or any other outwardly expressed motives. The entire basis of the moral claims to perform erotic acts with one another is a (mutual) desire to express intimate feeling in a physical manner at that moment. It is possible however that this desire will include damages and harms to unrelated parties to the event itself, such as legal spouses or previous pair bonds that are non-mutually dissolving. I can also make no determination that such actions should only be made between heterosexual couplings, or even couplings solely limited to two party sexual acts or any one particular variety of said couplings. Where homosexual or multiple partners or positions are deemed unacceptable by one party participating, presumably unwillingly, then it is indeed a moral failing. If the actions are consented to, which is admittedly not a common occurrence for all such variations of sexual activity, it is not.
2)Likewise, while I feel it is appropriate morally, such physical actions by persons both mutually below such ages of consent are often little more than experimentation. Such actions would still reach a moral basis on the grounds that they are physical actions between consenting persons for the purposes of mutual physical pleasures. It could be assumed that an intimate bonding as labeled above would include such a lesser purpose as mutual and temporary pleasures.
3) Persons wishing to provide physical pleasure to another party for the purpose of extracting some favor in return. This may vary between an expectation of reciprocation at a later time, expectations of romantic or other intimate bonds to be formed that have not yet as expressed in either sexual or non-sexual ways in the future, or a simple extraction of concessions in the form of property.
4) Persons wishing to procreate. Biologically this is indeed of central importance, but given human proclivities to sexual activity, it's not exactly central to human behavior. Nor is it deemed essential to human pair bonding for the purposes of recognizing our intimate bonds through the state mechanisms (ie, legal contracts like marriage) or our social institutions and rituals. As such it should not be elevated morally above other purposes. But because it involves moral decisions regarding the care and division of labour concerning the creation of new life, it should still carry some weigh upon our consideration of the act itself as a generally good and decent act. Providing it follows the moral imperatives expressed above it. To the extent that this can be done naturally, it follows that the parties involved would be of opposing sex and in each others physical presence at the time and ideally observing some standards set forth above. To the extent that human beings have developed artificial methods, it does not require all of them, though perhaps at least the third standard would apply, with at worst a concession of property for the donation of biological material for the purpose of breeding it with others.
5) persons expressing fantastic acts only through a mental state and without willing partners being present. I place this here not because it expresses some immoral quantity of action but because it lacks much moral potential at all to internalize our desires without an accompanying sentiment of real action afflicting other human beings in those desires. There is a moral quality where these fantastic settings are visually accompanied, such as to violate the actual privacy of others or to demand and seek the debasement of others (in an only partially compensated manner) for private amusement. But this is not a requirement of such activity in the same manner that non-consensual acts are not a requirement of partnered sexual activity.

of the more immodest qualities, which I hesitate to so rank
1a) persons imposing their will upon unwilling or non-consensual participants for the extraction of their own physical or emotional pleasures at the expense of the pain, suffering or humiliation of others. This would include most mature-immature sexual consorts but probably not most immature-immature consorts.
2a) persons extracting physical pleasures from others with no expectations of reciprocation in any manner and no performed act to compensate these demonstrations on the part of other parties.
3a) violations of privacy or dignity without compensation or participation clearly expressed in a consensual manner (such as recording or viewing the private acts, of any kind including many or most non-sexual acts, of others without consent).
4a) non-consensual reproductive demands. This would include only intentional actions designed to defeat birth control methods being undertaken by one or both parties under mutual arrangements, or at least arrangements demanded by one party to the act, previous to the act itself. "Accidental pregnancy", that is non-mutually planned and desired, and its related child bearing is common enough and contains, usually, no malicious intentions or designs.

I would think these sentiments are easily described by what they signal to the various parties involved
1) respect, admiration, affection
1a) disrespect, abuse, power
2) desire, appreciation, respect
2a) power, abuse, coercion for private interest without due consideration
3) coercion involving mutual interests
3a) abuse, disrespect, invasion
and so on.

Primarily why I bother to enumerate things like this is to get people to realize that what we consider rather simple ethical problems are not in fact very simple and straightforward in the forms and judgments to which we must apply them in real life. The basic virtues of respect and affections and consensual aims are easy enough to recognize in practice. But they must be consistently applied rather than the haphazard means usually deployed to establish societal rules, most commonly through "revealed" ethics as laid down by cultural heritage and tradition. Tradition, where it has established effective rules, should only be forcibly maintained where those rules portend to the establishment of a just society and permit reasonable and consistent actions on the part of its citizenry. Hypocritical or incomplete traditions, such as those which establish and maintain supremacy rather than recognize some basic level of equality and dignity for example, should be consistently re-examined to discern their utility.