What would be the harm?

[The Grand Nudger]

Can I add what I think would be a realists perspective (at the very simplest level), just to make sure I'm following?
1. Ends are goals
2. The means to an end describe instrumental value

These are consequentialist.

3. objective morality isn't a value proposition but a statement of intrinsic value.

All moral systems are propositions regarding value, not all moral syustems (even realist systems) are exclusively about intrinsic value.  Consequentialism often sides in practice (if not in theory) to instrumental value.  The value of something to point towards or reach for "the good" - not necessarily that the thing being done is good in and of itself.    Non natural realism also does this, proposing that natural things might be tokens of and good-for, but not the thing itself.

4. Moral objective good/bad, isn't about value either but about it's intrinsic value

This one will ring more for virtue ethicists than consequentialists (and it needs revision, it contradicted itself from one breath to the next).

5. Oxygen is a thing that can be good or bad based on your value and goal, but aside from your value and goal we can measure oxygen objectively

More that we can measure it objectively, and it has at least some objective value....though, it's more used for an analogy than to make a moral case.  To make a moral case by oxygen, consider depriving someone of it.  

6. Morality is objective  like oxygen in that it is measurable thus a hard fact

Can be, not is.  Can be.  Realists accept that not all moral evaluations are objective or fact based.  
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Something close to that, for us less classically trained?

Yea, sure, you get the thrusts here and there, but there isn't a single realist position beyond each different positions underlying realism.  There are disagreement as to the nature of that real thing, the best way to know about the real thing, whether or not we can know..or know enough about that real thing, and the best way to..i suppose I would say test for effect, in whether we stay close or stray to that real thing.