1. OK women do want variety, however naturally in most men the need to move around IS stronger. In evoloutionary terms the female clings to the male in order to ensure that the kids are brought up with their father, who will teach hunting/sheltering/*insert macho action

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Well firstly, just because something is some way because of biology doesn't mean that it should be that way.
Secondly, if you're going to talk in biological terms, you can scrap open relationships right away. Biology favours approximately seven-year monogamy. Biologically speaking, it's a good idea for women to be able to rely on their partners' fidelity (so that their resources are not divided between several sets of offspring), and it's good for men to be able to rely on theirs (so that they can be sure of not raising someone else's offspring). That means mutual fidelity is a good idea, from the point of view of evolution. There are strong biological drives behind the feeling of sexual jealousy.
It's less of an issue now that family planning is possible and desirable, which is why open relationships are acceptable. Having a happy open relationship is all about
rising above your biology. If you are to leave your sexual jealousy at the door, you must leave your gender stereotyping there too.
I can tell you now: there are
plenty of women inclined to have lots of sex with lots of different people. Do not use your biology as an excuse.
2. I'm not talking about discarding, I'm saying that certain people may find the same person over and over sexually boring (if that is one of the main pillars of the relationship)
They may, but while that's their business, I'd suggest that such an attitude is not a particularly mature one.
3. I keep myself and others aware that some relationships I am in are driven sexually, I'm not going to blame myself if people can't keep responsibiltiy for their own feelings, if they have this idea that from the first time we meet my intentions are to find a house with a white picket fence and.... you get the picture. It's my responsibility in the realtionship, to comfort them and interact and have fun, develope a connection, not too live up too their hopes and dreams. I am what I am, people of this world who have high sexual value say no more than they say yes. Female supermodels are desired by men all over the world, but the supermodels choose to say no.
I'm not sure what the latter part of this paragraph is about.
What I will say is that yes, it is your responsibility to be a good partner, and that means that you must be honest, responsible, and caring. You can, of course, have sex with whomever you choose, as long as everyone's happy about that, but you have a responsibility, as we all do, to respect others' feelings and remember that sex does make people feel things. It is an emotional experience for many people. And if you decide to have sex with someone, you have to accept that you may well inspire some feelings in them.
I do not like the cold individualism that I see at the centre of your post here. You will just punch the air, and if anyone gets in the way of your fist, that's their fault! People's feelings are fragile. Many people's neuroses revolve around sex. You need to keep in mind that people sometimes do things for the wrong reasons, including getting involved in sexual interactions. It's important to take care to ensure that the people you have sex with will not be hurt by the experience, and give them enough of your time and affection to ensure that they do not feel used or discarded.
I'd also add that I hope you find that the sexual encounters you get the most out of are the ones where you are not simply using the other person as a tool for masturbation, but where you are interested in their pleasure and you really want to make them feel good.
4. I've always felt wierd about raising kids or getting married with multiple people, it doesn't feel right to me, but I guess everyone has their own choices too make. For me commitment means to put you're undivided attention on one person and ensure that you make them as happy as possible.
I think that, for me, I will always be happiest knowing that my partner can see other people. So being in an open relationship is, for me, part of making my partner and myself as happy as possible.