Actually we do in fact have iconographic tombs which figure prominently in the Good Friday - Holy Saturday - Paschal liturgical cycle. We also have bronze snakes on our Bishops crosiers. I am not sure these could be regarded as essential as opposed to part of the local liturgical traditions of the East, but we do have these items in case anyone asks, so that has the amusing effect of unwittingly bypassing your first argument. Orthodox liturgical accessorizing is actually quite epic: in the different Eastern rites one will find spears for piercing the bread to be consecrated in the Eucharist, metal stars placed atop the carefully prepared bread, a variety of different types of veils and corporals, in the Syriac rite, liturgical slippers; there exist in Ethiopia replicas of the ark of the covenant and the ten commandments which function in place of the Antimension of the Byzantine Rite or the Tablitho of the West Syriac. There are various paraments that cover the antimension or tablitho.mmThe Ethiopians have liturgical umbrellas. Then, there exist a fairly vast assortment of materials for use on various liturgical occasions, some of which are perishable.
One could spend an infinite amount of time and money documenting the vast array of acoutrements which exist, which is a reason why the Islamic destruction of Christian churches in Syria and Iraq is so tragic; these are not cookie cutter institutions but rather, individual parishes might have distinct liturgical heritage, and the hardware to support that heritage.
However you are quite wrong to accuse the Orthodox of being theatrical. Actually a huge amount of the vast arraybof liturgical hardware I just alluded to is never really seen by the laity; for example, Coptic priests keep the instruments used for handling the Eucharist out of sight in a linen bundle on the altar table and are reticent to discuss its content. The Byzantine Rite Liturgy of Preparation occurs in silence, behind the iconostasis. These liturgies are not ritual magic, but they are important and extremely solemn forms of prayer. The majority of what a parishioner sees and hears on a given Sunday is invariant.
Now, on the point of tradition being Tradition because we say it is, this is of course correct because the Orthodox Church is the Apostolic Faith. It is by all practical definitions both foolproof and error-proof. Such objections as yours have been raised before, and they have always been due to human error.*
* I will readily admit to paraphrasing HAL 9000 with a certain relish.