Christianity is about happiness because life is about happiness, as Pascal perceived - but the Christian must know his condition to be wretched - wretched and yet also with hope.
Nonetheless, wretched as we are, many Christians have had the blessings of revelations and miracles to confirm and sustain their faith: revelations (divine communications) to answer problems or provide guidance; miracles of many kinds.
These might be called subjective revelations and miracles - they are real, but they are not meant to be communicated.
Everyday revelations and miracles are personal, and seem intended to be personal - but the Christian faith, on the other hand, was set-up and built-up on public, objective miracles and revelations.
The miracles of Christ were necessary to show that he was a supernatural being. The miracles did not show what kind of supernatural being He was, not even that He was good (since evil miracles occur - or at least pseudo-miracles which can fool humans).
The revelations of Christ's teaching, the teaching of the Apostles and Holy Fathers - these were necessary to establish the Christian Church, and to correct its distortions and corruptions. Again, like the early miracles, these were 'for public consumption'.
But at this stage in the plan of salvation - the End Times, or something close to them - there have not been public revelations and miracles for some generations. Indeed, we are now (at least in The West) feeble in our faith and corrupted by worldliness, so both the average and peak levels of sanctity (or theosis) are much much lower than they used to be. Thus we could not understand major revelations and would misinterpret them, and we would disbelieve and argue against even major public miracles.
But the good news is that even we modern, feeble practising Christians are granted personal, private revelations and miracles. These are of immense value in sustaining our faith and guiding our lives, but are not meant to be communicated, nor should they be used as proofs of Christianity - and certainly not put forward as reliable benefits of becoming a Christian. They are not earned!
Private revelations and personal miracles would not convince skeptics, that is not their purpose - indeed the chance to 'disprove' them by offering alternative explanations would probably reinforce skepticism.
We need to distinguish between that which is given us by grace for our own benefit (and the benefit of those we love) which is as much a part of private discourse as the endearments of family life; from the large scale, public, overwhelming, faith-establishing events of the earlier church.
But while refusing to talk about our private revelations and personal miracles with any specificity (just as we would refuse to describe the specifics of our married lives), we can and should acknowledge their reality and importance, and be very thankful for them.