The Church does not assign an essential difference between praying before the tabernacle and praying before the Lord when displayed in the monstrance in Eucharistic Adoration. A Vatican document on the Eucharist says: “Exposition of the blessed sacrament, either in a ciborium or a monstrance, draws the faithful to an awareness of the sublime presence of Christ and invites them to inner communion with him. Therefore, it is a strong encouragement toward the worship owed to Christ in spirit and in truth” (Eucharisticum Mysterium, No. 60).
So, both forms of adoration are commended. But while there is not an essential difference, there can be a subjectively different experience. In adoration before the Blessed Sacrament exposed in a monstrance, there is a visual aspect that helps many to stay more focused. In this sense one may argue that Eucharistic Adoration before the monstrance is “better.” But as you point out, personal factors such as schedules or a preference for quieter, briefer or more solitary visits can also influence what is better.
The bottom line is that the Church encourages devotion to the Blessed Sacrament. Such devotion, through visits, adoration, signs of respect through kneeling, genuflection and making the Sign of the Cross as one passes a Catholic Church, all acknowledge the sublime presence of the Lord in the Most Blessed Sacrament.