One can't generalize believers' worship into fundamentalists, unless the point of your posts is specifically aimed at fundamentalists. The don't exactly make up the majority of Christians. Not to say they lack numbers, but one can't (though people do) base all Christians on even one larger group.
The step a Christian must take towards true worship--true acknowledgement and respect toward God--comes in the way the life is lived. Which doesn't mean we ought to be satisfied by saying Oh yes I was born with the purpose of worshipping God. It's too vague. It beats around the bush. It avoids the lesser known depths of what to do with that kind of knowledge.
(An acquaintance once said to me, regarding her taking a couple months to serve a mission, "I was going to go to Thailand, but then God changed my heart." She lashed out when i asked what that even meant. The story isn't what took place before and after the "change of heart" but the process of that act. Asking one's self what that means--that's the kind of God lingo I think people are too often afraid to define or elaborate.)
Let's take Jesus. It's no secret that he rarely told someone without ambiguity how to live. His compassion was in his actions more than his words, with big exceptions like the Sermon on the Mount, when he put it all out there. Jesus represented the first moments when Jews were taught to see how to really live. Apostles and disciples watched his actions as much as they heard his words. Perhaps he literally touched and healed the leper, but in our modern world the same act could be "emotionally" healing--a person who lives with people afraid to touch him/her suddenly meeting someone unafraid to hold their hand. That's amazing. That makes people think and speaks much more than words.
People can live their entire lives as believers and have no way of letting people know of it--people might never guess. There came a point when I decided to challenge myself: to figure out how I could be that human manifestation of what I believed. To be that link between beliefs (which many share) and the world. This search, as uncertain and mysterious as it can be, is the purpose. God doesn't want us to sit in church and worship him, or to pray at night before bed or at dinner and call it a day, or even to just read all the right books for personal comfort. He wants us to examine our own passions and choose to offer them to him (a tough choice, a sacrificial choice, but a choice nonetheless). Then take a leap of faith into something that feels right because why should we follow a path that doesn't give us that feeling of rightness? (I realize people too often do, and I or you one day may, but the question should still be posed.) I think any denomination, once you get to know it, will encourage this. It's a unifier.
The entire experience satisfies the ego to an extent, yes, because that sense of purpose starts to be fulfilled. But it's also humbling to the individual, the act of which on the personality has the antithetical effect on the ego. And one can't tell me that even atheists don't try to feed the ego. Existential psychotherapy is founded on the basis that there is no higher being and no grand meaning, but that the therapy is designed to teach people to create individual personal meanings. To say that religion alone inflates ego is absurd.
Science perceives and accepts the fact that our knowledge has limitations, and works towards overcoming them if possible.Emotion instead tries to fill in the gaps with imagination and plausible stories that look pretty.
When mankind was grounded, some imagined man in flight.
When mankind was limited to earth, some imagined man in space.
When the world was flat, someone imagined that it was round.
When the earth was the center of the universe, someone imagined that it was the sun.
Imagination is not simply a tool used to deal with emotion. It drives science as well. Science has its own gaps to fill, and gaps to create, just like emotion (and to move back to the main point, purpose). Imagination and stories aren't always used to satisfy; as often are they used to compel--"to force or drive, especially to a force of action."
A mentally unstable god, with tendency to rage and abuse, and theatrical self-sacrifice... sorry, i want nothing to do with that.
"Mentally unstable" sound like a clinical term. "Unstable" is an adjective, and one that can even describe lapses in the average person's common sense. Moments of anger, of hate, of frustration or even annoyance. But there is always the joy happiness calmness felt. You can't deny that we feel the spectrum of these things.
To worship God for perfection makes a distance between you and him, draws an unattainable image; to worship him as a creator makes you look around and see all that is created. A God we can relate to. Just because the idea that God feels sadness and jealousy challenges you doesn't mean he wants you to turn your back on him. A hardened mold he can no longer fit would simply need changing. The Bible is very straightforward about his emotions and the results of them.