are there now, or have there ever been catholic priests/bishops/etc.etc. who have been heavily involved in child abuse, or the covering up of such crimes?
Yes, yes there have, something that continues to this day unfortunately
Have members of the catholic faith partaken of serious sectarian violence of all kinds against members of other faiths, including against those of other christian faiths?
Yes, yes they have, indeed this too still happens to this day
Is catholic religious architecture (i.e. churches, etc.) actually quite interesting, nay somewhat fancy at the highest levels of the faith?
Yes, yes it is, and this isn't a criticism either, interesting/fancy architecture should always be studied and enjoyed
And yes, the same points could be said for most if not all of the worlds major man-made religions, so not to just pick on catholics in general, but needing to believe in some imaginary invisible supposedly all-powerful being dreamt up by a small group of men on a powertrip thousands of years ago in order to get you through the day and guide you between right and wrong is nothing more than the classic sign of a weak-willed sheep.