How closely aligned are Buddhist ethics and Nietzschean values?

Nietzsche's philosophy, on the contrary, is ultimately self serving, even aggrandizing

I tend to agree.

One thing I notice is that Buddhist licentiousness seems to breed a similar sort of arrogance (nb Buddhists accuse each other of this at times), the same sense that the suffering of others is their obligation to us. We are free to choose our values in both of these philosophies, just as some individuals are better set to do so (even authentic milk is different to authentic butter).

It may be that the Buddha meant that all ethical judgments are in error, and it may be that Nietzsche merely meant that all moral judgments are fictional. But, either way, you should surely take it on a case by case basis, either in the abstract (Nietzsche belittles Mitleid) or in the concrete (the Buddha suggested his followers completely abstain from intoxicants).

So, apples and oranges: at least they're not vegetables.

Most philosophies seek greatness in someone.

Nietsche does agree with the Buddha on some things. They both point out the problem of self:

Nietsche: One must not eye oneself while having an experience; else the eye becomes "an evil eye."
MN62:3.2: “Rāhula, you should truly see any kind of form at all—past, future, or present; internal or external; coarse or fine; inferior or superior; far or near: all form—with right understanding: ‘This is not mine, I am not this, this is not my self.’”

However, there is profound disagreement on immersion. Nietsche's "frenzy" corresponds to wrong immersion for Buddhists.

Nietsche: in this state one enriches everything out of one's own fullness: whatever one sees, whatever one wills, is seen swelled, taut, strong, overloaded with strength. A man in this state transforms things until they mirror his power--until they are reflections of his perfection. This having to transform into perfection is--art. Even everything that he is not yet, becomes for him an occasion of joy in himself; in art man enjoys himself as perfection.”

The Buddha declares right immersion as:

AN5.28:2.1: “And how do you develop noble right immersion with five factors?
AN5.28:2.2: Firstly, a mendicant, quite secluded from sensual pleasures, secluded from unskillful qualities, enters and remains in the first absorption. It has the rapture and bliss born of seclusion, while placing the mind and keeping it connected.

I've tried both ways. The Buddha's way leads to less suffering. YMMV.

Not closely aligned at all. Nietzsche believes in "the will to power." The Buddha teaches the path to the relinquishment of "will" and "power," so that the endless march to attain these two things, "what one wants" (will) and "the pursued ability to get what one wants" (power) are utterly pacified. The Arhat is happy even in the nastiest of circumstances. He has no desire to change his material circumstances. Why? He has the secret happiness available to him that all Buddhas have, the ability to dwell in Nirvana, the "highest happiness."

As much as Zen is related in aim and way: not at all, aside of a prove that defilement have endless arguments to hold on wrong at the base, good householder.

Yet even former wanderers under either Zen or Nietsche, hardly ever arrive at the Dhamma and will still relay on wrong view, making "I have a right" to their incapacity's. into a virtue... blessed who never nourished in this sink of dung, to be smelled from far by wise.

They aren't aligned at all. Nietzsche's critique of Christianity could just as easily be levied against Buddhism. The only reason I think that he tepidly praised Buddhism is because he only understood it as a philosophy, not the soteriological religion that it undoubtably is.

For instance - "The Christian faith from the beginning, is sacrifice the sacrifice of all freedom, all pride, all self-confidence of spirit, it is at the same time subjection, self-derision, and self-mutilation."

Buddhism, at its core, is a religion of self sacrifice. The first paramita is dana. We give not just alms or service but make a wholehearted offering of our very being. In Zen, we celebrate dying on the cushion. In the tantras, you give over everything to your guru. In the Theravada, there is the model of leaving home and everything behind. All of these are examples of self subjugation. Nietzsche's philosophy, on the contrary, is ultimately self serving, even aggrandizing.