http://www.vatican.va/news_services/liturgy/details/ns_lit_doc_20091117_crocifisso_en.html

On the matter of the altar crucifix, which has bugged me for months now, can liturgists be empowered so that they can indeed persuade the priests, in coordination with the bishop of course, to put such a beautiful, reasonable, and meaningful arrangement? 

As altar crucifix is for the priest to use, and is no barrier to the faithful as many would have countered, and we should indeed glory in the cross of Christ, and not be ashamed at having it. The other, usually larger altar crucifix is for the rest of the congregations to see. Naturally, as in many post-Vatican II arrangements, these crucifixes are placed such that the priests can no longer see them.

It is crucial that everyone, and including the priests, focus their attention to the Lord, represented in the altar crucifix, as the interior alignment/orientation and condition of the priests are important in their celebration of the Mass, that their attention is not to themselves, and not to other things, but towards the Lord. 

http://www.hprweb.com/2012/01/cross-altar-and-the-right-way-of-praying/

In the old days, this is no problem since everyone is facing the Lord, but in our modern arrangement, there is no better solution than that of the “Benedictine” arrangement, by our beloved Pope Benedict XVI himself, that an additional altar crucifix should be used on the altar if the priests cannot see the large crucifix behind the altar intended for the congregation. 

http://www.vatican.va/news_services/liturgy/details/ns_lit_doc_20110126_crocifisso_en.html

That this is the new “Ad orientem” (literally means facing east, as traditionally, Christians pray facing east, towards Jerusalem), which is indeed, facing towards God, in Jesus, for the people, and the priests (celebrant and concelebrants alike).

Similarly with the traditional 6 candles arrangement (7 for bishops), bowing at the Name of Jesus Christ, at the Incarnation moment of the Creed, and many others. There are meanings to all of these, and these are not just ornaments, but articles and things that can help deepen the faith of all who participate in the Mass, if the priests explain them clearly, and together, through the liturgy, our faith can only be ever stronger.