A good mood/satisfaction

You have 6 sense doors with the 5 inclined towards external senses and the the mind. Whenever anything comes in contact with any of the sense doors a sensation arices. It is like a stone thrown to water. E.g. if you see something 1st a sensation occurs around your eyes which nearly instantly ripples to your brain area when you give it an evaluation and both this ripples throughout your body.

How you fulfill a desire is that you seek some form of external or mental stimulation or contact which triggers some sensation which you have give a evaluation as something you desire or avoid contact with something you have given an evaluation as something you do not desire. Not relating to any sensation arising from contact you stop clinging or seeking to desire. If something pleasant comes your way well and good. If it does not still no issue. Wanting more is the issue here. If you want something more and do not get it you are disappointed. You have to get your mind to a state where you do not get disappointed whatever happens.

Regarding characteristics of pleasure & pain, MN 44 says this:

Pleasant feeling is pleasant in remaining, & painful in changing, friend Visakha. Painful feeling is painful in remaining & pleasant in changing. Neither-pleasant-nor-painful feeling is pleasant in occurring together with knowledge, and painful in occurring without knowledge.

Regarding your sleepiness: once the need arises, I'd try to substitute some of it for meditation, trying to focus on the breath, and not go anywhere else in your mind. Just sticking with it.

If you can get yourself to a state where you can enter meditation and gain refreshment and enjoyment, you'll have made very good progress, and that choice will now be more readily available to you wherever you are. But like anything worthwhile, it takes persistence and dedication to attain. So try to use this motivation for rest that you have right now as a catalyst for developing good qualities.

Sleep feels like pleasure when it is stress-free and the waking life is stressful. But a state of stress-free wakefulness is a higher bliss than sleep.

In your case the easiest way to achieve that should be through getting fed up with highs and lows, as opposed to suppressing them. This does not mean you have to deliberately seek the highest highs and the lowest lows but you don't have to particularly hide from them either -- this is a Vajrayana perspective. Instead, just face your pleasure directly, experience it fully, and see to what extent it is really a pleasure -- and at the same time see if you can open your scope enough to notice an element of pain that always accompanies pleasure: the pain of urging for more, the pain of interrupted pleasure, the pain of overindulging, and the pain of the high itself.

When you see that pleasure is not as pleasurable as it seems superficially, you will naturally get over it. The same way the "lows" are not as real as our minds would like us to believe. Once you really get this then you can sincerely and honestly experience whatever happens, without getting obsessed with its either so-called "pleasant" or "painful" qualities which are never as stable nor as separate from each other as they seem; they contain each other and fluidly flow into each other like Yin and Yang. Then you can naturally stay calm and blissful (dynamically transparent and open, rather than frozen) throughout all experiences.

Usually, when we get tired we calm down. When we calm down, our sensitivity naturally increases, and that's what you project as sensuality. But you don't have to get tired in order to calm down, nor do you have to limit your use of sensitivity to sensuality only, you can use it for all kinds of things.

Now, the reason we usually get sleepy when we calm down, is because the mind is conditioned to the drama of highs and lows, and when there is a gap it turns itself off. If you can get used to staying fresh amidst the calmness coming from openness, you can make good use of the increased sensitivity -- you can be an artist, a poet, a visionary...

I've read that to not experience any desire is greater than fulfilling ones desires. Is this equality 'simply' achieved through mindfulness? How would you recommend pursuing this?

I suspect it's through Right view.

For example you may notice that desires aren't satisfactory or aren't satisfied: that you cannot have what you want; that you do not want what you have; and that the things you already want and have, you cannot keep.

Or you might notice that wanting things to be other than as they are can be delusional, unskillful.

There is such a thing as "mindfulness", but it may be (i.e. I find it is, historically) helpful to see them in the sequence in which they're given:

• Because of your view you develop intention
• By (resulting from) intention you develop effort
• By (resulting from) effort you develop mindfulness and concentration

But the 'view' comes first, and the rest are because of view.

Not that moderation is impossible, but its hard to draw a line with pleasure that is truly satisfying.

Maybe the pleasure is in successfully satisfying a need. If I am (my body is) tired and need to sleep then sleeping, relaxing (which satisfies that need) can feel "pleasurable". After a good night's sleep, I don't need to sleep any more.

Also maybe you don't need to draw a sharp/precise line: meditate before sleeping, dream of meditation while asleep, wake up to meditation.

IMO Buddhism is not averse to satisfying your bodily needs: see for example Buddhism and the body.

See also Middle way: "In the Pali Canon of Theravada Buddhism, the expression Middle Way is used by the Buddha in his first discourse (the Dhammacakkappavattana Sutta) to describe the Noble Eightfold Path as the noble path to achieve Nirvana, instead of taking extremes of austerities and sensual indulgence. Later Pali literature has also used the phrase Middle Way to refer to the Buddha's teaching of dependent origination as a view between the extremes of eternalism and annihilationism."

One of the things that makes physical pleasure (from satisfying physical needs) 'unsatisfactory' is that it's temporary: e.g. after you have eaten enough, then it is not pleasurable to eat more.

Are some pleasures more satisfying? Or is the only path to satisfaction enlightenment, being detached from desires?

How about the pleasure of having no desires?

Another way to express that is having the ability to fulfill your own needs. Part of doing that successfully is to ensure that your needs are humble. There's an expression from Zen, "Eat when hungry, sleep when tired."