To concentrate on 6 and 7, then.
7 first : the only consensus, or anything approaching a consensus, centres on there being three basic approaches in ethical theory : (1) the deontological, which is concerned with duty and with what is intrinsically right or wrong regardless of consequences; consequentialism, usually in the form of utilitarianism, which takes rightness or wrongness to be wholly a matter of consequences (actual, probable, expected ...); and virtue ethics, which focuses on traits of character, virtues, the possession and exercise of which are seen as an essential part of human flourishing.
It's possible to draw lines of connection between the three but they are not, at least on the surface, mutually reducible. These are three broadly distinct and incompatible approaches to ethical theory.
This might appear, and is, an untidy state of affairs but there is no consensus that any one theory is the correct way of doing ethics; there is only a loose consensus that these three are the main approaches. (My own view is that no single ethical theory is adequate to the real complexity of the moral life and that different theories need to triangulate - divide - the ground between them. No-one agrees with this.)
Some philosophers would want to include a fourth approach, that of rights-based ethical theory. There's a case to be made for this but I don't think - I could be wrong - that rights-based ethical theories have quite established equal influence to the other three.
6 is really interesting. I think it will always be the case that novel types of moral situation will arise which, in its then current state, no ethical theory can adequately handle. The unfamiliar and the extraordinary are always in the wings. Issues of ecology and gender define such issues in our own time. No ethical theory has, for example, a fully comprehensive and consistent response to the nature of a person's gender under conditions of gender dysphoria. What is my 'real' gender when my psychological and emotional gender do not match my biological gender ? Is there any such thing as 'real' gender - or 'gender' at all ? The answers to these questions all carry ethical implications, implications for how persons should be treated. Yet none is up to speed on bio-ethics.
How do, can or should ethical theories self-revise in face of such situations and issues ? There is no answer peculiar or special to ethics here. Ethicists need to adopt whatever theory of rational belief revision best commends itself to them. It is impossible to expand on this topic here except to mention Rawls' notion of 'reflective equilibrium', as one approach to how to conduct belief revision in ethics. See J. Rawls, 'A Theory of Justice', Oxford: OUP, 1972, 10; and N. Daniels, 'Reflective Equilibrium and Archimedean Points', Canadian
Journal of Philosophy, 10 (1980) 83-101 & 'Reflective Equilibrium and Theory Acceptance in Ethics', Journal of Philosophy 76 (1979) 264-73.
Tom Sorrell deals with 'moral anomalies' - situations and issues that ethical theories cannot deal with adequately in their prevailing state - in 'Moral Theory and Anomaly', Oxford : Blackwell, 2000.