I am a former Catholic who left out of annoyance at all the layers and structures in the Church. Would the apostles recognize the simple and humble Church they had, compared to the pompous and ceremonial church of today?

Well, I am not so sure. It's kind of like asking if Orville and Wilbur Wright would recognize the simple wooden and cloth plane they flew, compared to the modern jetliner of today. To some extent they certainly would see the basic structure, but they would also marvel at all the magnificent developments that their simple idea has ushered in. 
 
It would not be reasonable to assume that they would wag their finger and insist we go back to planes made of cloth and wood and gasoline motors. It seems more reasonable that they would admire the developments that have ensued, all of which built on the basic ideas that they set forth. 
 
I think it would be similar with the Apostles. It is clear that doctrine has developed over the years, as has liturgy and other necessary structures in the Church. But these things developed from the structures that were already there from the beginning. The seed of truth has become the mature tree. The hierarchal structure, established by Christ himself, has expanded to meet the needs of a now worldwide Church. 
 
You are free to consider things you don't like as pompous, but others see such things as dignified and appropriate. God, and the things of God, are rightly to be honored with some degree of ceremony and respect.