Welcome, Gareth. I'm really glad you stopped by the website. First off, please don't feel you need to apologize for being passionate (or heated as you say). These are serious issues which we should be passionate about. I really appreciate your honesty, and I hope you will come back and continue to share your objections and concerns.
I'm not your typical Christian, and I try very hard not to be the kind of "super-religious" person who goes around telling people they need to believe or they're going to hell. I was not a Christian for much of my life and I know how that kind of nonsense turns people off, so let me just share how I came to believe in Jesus, and I hope you'll continue to let me answer some of your questions.
I didn't come to believe in Jesus directly. If you approach it that way, it sounds too absurd - a man lived 2,000 years ago, was raised from the dead and I need to worship him or else! No, too much to deal with head on. Instead, I realized there are certain facts that demand an explanation. For example, I have to account for how life came to exist in this universe? Chance? Maybe, but honestly the most reasonable answer is a creator. I have to account for the "moral law" which for the most part, compels people to want to do good (even though we often fail to do the good we are compelled to do). A benevolent God is the most reasonable explanation for this. I have to account for the fact that over a billion people believe in Jesus. Now, the fact that people believe in a thing does not make it true, but it does make that thing worthy of my investigation. And so, when I investigate the evidence for Jesus, I find it extremely compelling. Finally, I have to account for the fact that almost everyone, since the dawn of time, has felt drawn to a belief in God. Many people reject this or ignore it, but I think everyone feels it. I believe that you feel it on some level, or you want not have posted here. Forgive me for being so bold, but if you believed 100 that God does not exist, you would not have come to this site. Instead, you would not have even bothered wasting your time.
So, when I consider all these things that demand an explanation, I find that God is the most reasonable explanation. It makes sense to me. Sure, there are lots of parts that don't make sense, but I don't throw out the entire concept of God just because some parts don't add up.
I really hope some of what I've written is helpful. Please come back and let me know if there is anything else I can do to help convince you, if not that God exists, then at least that it's worth spending time investigating. I hope you will let us help you with that investigation.
Last but not least, may I pray for you? I will pray that God will reveal Himself to you just as you've asked. I could never promise that he will, but sometimes he surprises us. I will ask him to do just that. Have you also asked him? He would love to hear it from you.