Home shrines are memorobilia and symbols that help us focus ourattention and recall mystical experiences.
The items in the shrine are holy in the true sense of the word, which means "dedicated to the divine". Those items and the shrine itself has no other purpose, it is dedicated to serving us to recall the many aspects of the spiritual life to come and the changes we must make in ourselves to get there.
Perhpas like someone who put up a poster of a Carribbean beach, as a reminder to help him focus on his goal to save for that trip. He saves and looks at the poster dreamily, wishing he was there already. Because he is saving, he knows that ay will come and one day he will walk on that beach.
People are different and make different use of shrines. For me, I talk to the Lord and the angels all the time. I say good morning, sometimes I remember tosay good night. Its pleasant company for me in meditations.
Some people use shrines to direct their energies to loved ones in need of care or healing. Some use the shrine to retreat to a simplicity and humbleness.
In Thailand and several other places, as it should be in your home too, images of spiritual beings like buddhas are never used as a decoration. Those images must never be placed on the floor, must always be elevated even i only a few cm. But here is the underlying ethic, images of spiritual beings and heaven must be treated with due respect.
In Thailand for example, one can go to jain for disrespecting a buddha. Many foreigners were arrested, had their visas cancelled and were fined for having totoos of a buddha that was deemed disrespectful because they were not used as shrines but as decorations.