I tend to use words in their original meaning.

Not a bad policy. The trouble is that saying "my version of Christianity is rooted in the gospels" doesn't really do much to distinguish you from everyone else, because pretty much all Christians consider that their version of Christianity is rooted in the gospels. So describing your variety of Christianity as "evangelic" tells me rather little.

as I said, I think you might have misunderstood

Well, your actual words were "you seem to fail to understand important things about christianity". But it's OK; I'm not offended.

so you only hint at stuff

Well, you know, I did consider just asking you "so what kind of Christian are you?" and refusing to say anything about what might be the strongest arguments against any kind of Christianity until the kind is precisely specified. I thought it might help us move forward a bit quicker if I gave some indication of the kinds of arguments that might be appropriate, so that we could work in parallel on figuring out (1) what kind of Christianity to look for good arguments against and (2) what those arguments actually are.

Why would a christian need to be a hardcore fundamentalist and interpret the whole Bible literal?

They wouldn't. My whole point was that there are different kinds of Christians with different kinds of Christianity. One kind -- by no means the only kind -- is the hardcore fundamentalist who claims to believe everything in the Bible (not necessarily literally, but I never claimed otherwise). If I were looking for good arguments against that kind of Christianity, one thing I'd look at is inconsistencies between different bits of the Bible (that appear to be intended as straightforward history or doctrinal teaching rather than any kind of metaphor).

I guess you mean that this only apply to SOME christians.

Yes. If I hadn't already made that clear enough, I apologize. (I thought I had.)

Well, this seems like an ambitious statement in my eyes.

Really? You think a good default position is that Christians are spectacularly better than everyone else, morally? OK.

(I think the cross-country comparison you suggest is totally invalidated by lots of other things that historically happen to correlate a bit with Christian heritage.)

Why WOULD christians need to have higher moral? Where do you find that premise in the NT?

Christians are supposed (at least according to some varieties of Christianity, the ones I'd be taking aim at if I were making that kind of argument) to be indwelt by the Holy Spirit of God, who is the source of all goodness and value in the world.

Christians typical pray frequently (both individually and if following standard liturgies of various churches that have them) for their hearts to be purified, to be cleansed from sin, to be enabled to live righteously. This seems like very much the kind of prayer that the Christian god might be expected to grant, if he were real (it is clearly in line with his stated goals; it doesn't require "interference" with the world beyond people's minds; the minds in question are of people who have already declared themselves willing for him to change them, and are specifically asking him to do it.)

Like we have been very successful at definitely defining the universe for hundreds of years of scientific struggle.

Well, actually, we have. Spectacularly so. Do you really disagree?

[EDITED to add a few other things since I had to write the above in a bit of a rush, which is one reason why it's too long:]

Some suggestions in the NT that Christians should be much better morally than they generally are: 1 Peter 2 says that Jesus "bore our own sins in his body on the tree, that we might die to sin but live to righteousness"; one can read that as talking about some kind of "imputed righteousness" that doesn't actually involve acting righteously, but I think it's a stretch and more to the point a Christian of the particular kind I said this might be a good response to wouldn't take that position. 1 John 1 and 2 similarly talk of being "cleansed from all unrighteousness" and again I don't think it's likely that the author means some purely formal transaction that doesn't involve actually becoming morally better. He seems to admit only reluctantly that genuine Christians might continue to commit sins at all. In chapter 3 he goes further: "No one who abides in him sins; no one who sins has either seen him or known him." Now of course 1 John paints with a very broad brush, but there it is in the New Testament and even if the author is overstating his case he must mean something by it. That famous chapter that you recommended I should consider, 1 Corinthians 13: read it in its context; it is saying that love (with that whole extravagant litany of virtues it brings along with it) is the most important gift of the Holy Spirit that is supposed to be present and active within every Christian's heart. Galatians 5 has a lengthy list of "fruits of the Spirit" (which Christians are supposed to exhibit) and most of them are moral virtues (and the corresponding "works of the flesh" opposed thereto are mostly moral vices).

here are something to consider

I'm afraid it's not obvious what sort of conclusion you're hoping I'll draw from your list. Rather than guessing, I'll comment briefly on the individual items in it. I may very well be missing your point, though.

• The holy trinity ... seems to me a doctrine of doubtful coherence and at best ambiguous support in the NT documents that are generally reckoned the foundation of Christian doctrine. Some Christians contemplating it have had neat ideas (e.g., the idea that the love Christianity makes a big deal of is found within, so to speak, the very structure of the Deity). I don't see that Christianity is any more likely to be right, or beneficial, on account of having this idea in it.
• Jesus saying: I am the way and the life ... and the truth; don't forget the truth. Anyway, again I'm not sure what I'm supposed to be being impressed by here. There's a fair chance that Jesus's grand-sounding "I am ..." sayings, found only in John's gospel, were in fact made up by the author of that gospel -- don't you think they're the sort of things that the authors of the synoptic gospels might have been expected to record? So if you're working towards a "lord, liar or lunatic" argument then I don't think this is a great place to start. (Such arguments have other weaknesses, but I won't belabour them unless it turns out you really are making one.)
• The statement that Jesus is the son of God and [etc.] ... well, it's a statement. I don't find that contemplating it fills me with awe or certainty that he must have been who the NT writers say he said he was. Many other religions don't make similar claims about their founders; I guess that's part of your point; but I'm not sure where you're going from there. (Lord/liar/lunatic again?)
• First Epistle to the Corinthians, [chapter] 13 ... yeah, it's a fine piece of writing. So are some other things in the Bible. I don't see that they're supernaturally good, though, if that's where you're heading; I'm not familiar enough with other religions' scriptures to know how good their Best Bits are (though I know Muslims sometimes say that the sublimity of the Qur'an is evidence of its divine origin).