To attempt to summarize Homer's use of the subjunctive and optative is to embrace failure. All that remains is how splendid a failure it will be....
After much reading and some thinking, I find myself in the camp that regards the subjunctive and optative as kinds of futures. Thus, after Goodwin (and others), I would say that Homer has six ways of expressing futurity:
1. mere future
2. modified future
3. mere subjunctive
4. modified subjunctive
5. mere optative
6. modified optative
where 'modified' means accompanied by the modal particles [face=SPIonic]ke[/face] or [face=SPIonic]a)/n[/face].
One of the things that makes such a 'summary' so daunting is Homer's fluid and seemingly chaotic combinations of these six modes of futurity.
Much of this confusion arises from the 'when' of the Homeric language. In Homer's Greek we see a language whose modal particles
had not yet lost their original force. This loss was, eventually, caused by the well developed system of moods and tenses that Greek inherited from Indo-European.
That is, the subjunctive and optative began to take over meanings once imparted chiefly by these particles. But in Homer we still see them in promiscuous
combination not only with these moods, but with the future tense as well.
We might contrast this movement of modal force from particle to mood in Greek with the example of Hittite. There, apparently, a considerably less
developed system of moods and tenses failed to subsume the modal particle function.
By the way, the argument that the fundamental idea of the subjunctive is 'will' and that of the optative 'wish', comes from a German scholar named Delbruck. Goodwin does an especially good job of refuting this argument. This is not to say that there is no sense of 'will' or 'wish' in these moods, only that these are not essential components of the moods.
Within the subjunctive mood, then, we distinguish between the 'voluntative' and 'prospective'. The voluntative does indeed involve notions of 'will':
[face=SPIonic]mh/ se, ge/ron, koi/lh|sin e)gw\ para\ nusi\ kixh/w[/face] - "let me not come upon".
[face=SPIonic]i)/wmen[/face] - "let us go"
[face=SPIonic]mh\ i)/wmen[/face] - "let us not go"
The voluntative subjunctive is practically limited to the first person where, in the singular, it is often accompanied by some exhortation like
[face=SPIonic]a)/ge, ei) d'a)/ge, i)/qi[/face].
The voluntative subjunctive typically takes the prohibitive negative particle [face=SPIonic]mh/[/face].
The 'prospective' subjunctive either shows no notion of will or it shows a mixture of futurity and will:
[face=SPIonic]ou) ga/r pw toi/ouj i)/don a)ne/raj ou)de i)/dwmai[/face] - "For I have never seen such men nor do I expect to see."
[face=SPIonic]kai/ pote/ tij ei)/ph|sin[/face] - "and some one will say".
[face=SPIonic]..saw/terpoj w(/j ke ne/hai.[/face] - "so that you may return safer"
[face=SPIonic]..ta/x' a)/n pote qumo\n o)le/ssh|.[/face] - "..presently he will lose his life"
Iliad 1.262 and 6.459 are notable because they contain no notion of 'will'; they function as future indicatives.
But in 1.32 and 1.205 you can sense not just futurity but some component of interest as well.
The prospective subjunctive is often accompanied by the modal particle. But there are many exceptions to this 'rule'.
It typically takes the 'denying' negative particle [face=SPIonic]ou)[/face]:
[face=SPIonic]ou)k i)/dwmai[/face] - "I shall not see"
Parallel to the voluntative and prospective subjunctives are the 'wish' and 'potential' optatives.
[face=SPIonic]u(mi=n me\n qeoi\ doi=en..[/face] - "May the gods grant you.."
[face=SPIonic]ti/seian Danaoi\..[/face] - "May the Danaans atone.."
[face=SPIonic]i)/oimen[/face] - "may we go"
Like the voluntative subjunctive, the wish optative typically takes the prohibitive negative particle [face=SPIonic]mh/[/face]:
[face=SPIonic]mh\ a)po/loito[/face] - "may he not die"
[face=SPIonic]..ei)/ ken qa/nato/n ge fu/goimen[/face] - "..if we might escape death"
[face=SPIonic]o(/j k' ei)/poi..[/face] - "who could say.."
The potential optative is often accompanied by the modal particle.
Like the prospective subjunctive, the potential optative typically takes the 'denying' negative particle [face=SPIonic]ou)[/face]
[face=SPIonic]ou)k a)\n a)po/loito[/face] - "he would not die"
It is simply impossible to abstract from these cases a few simple rules to describe Homer's use of future, subjunctive, and optative. The general guidelines
Voluntative subjunctive and wish optative - no modal particle, negative is [face=SPIonic]mh/[/face]
Prospective subjunctive and potential optative - modal particle, negative is [face=SPIonic]ou)[/face]
Because there is yet no rule with regard to the use of the modal particles, the negative particle is often a sounder indicator, at least of
volitional force. That is, use the presence of [face=SPIonic]mh/[/face] as a clue to an 'interested' speaker.
I hope this is of some help.