The underlying theology for this devotional practice has undergone evolution. Since Pope Saint John Paul II, the preferred term is “act of entrustment.” This better expressed the matter.
Consecration is effected by God in definitive circumstances of liturgical significance and has an ecclesiastical dimension. In these sort of situations being considered here, it is applicable only by way of analogy and in an extended way.
When looked upon in this new vision, yes…you can certainly entrust yourself to more than one saint. Doing so may be, in fact, quite appropriate such as asking Saint Joseph of the Parents of the Virgin to be patron of one’s Marian devotion…or, for that matter, Saint Catherine Laboure, Saint Bernadette of Lourdes, or Saints Jacinta and Francisco Marto of Fatima.