The norm for reception of the Eucharist is on the tongue. In the US and most places in the west, an indult has been granted to receive in the hand. I used to receive in the hand, but since I have had children I receive on the tongue. Usually because my hands are full and it feels disrespectful to juggle the host and the baby in order to receive. Since then, even if I am not carrying a baby I receive on the tongue, unless I have a cold sore or am getting over some nasty cold and still have that hacking cough that hangs on a while. Though I will maintain that the priest touching everyone’s hands is no cleaner than him touching everyone’s mouth.
One of the reasons that many people argue that reception on the tongue is objectively more reverent, is that it reduces the obvious instances of desecration or sacrilege. Just this past Sunday I happened to look up as some old lady picked the host out of the priest’s hands rather than letting him place in it in her hands. It is also more difficult to take the host home after it has been in your mouth. So reception on the tongue probably isn’t more reverent for most prepared individuals, but on the whole it is more reverent, because it helps prevent some of these common abuses. (It, of course, won’t change the disposition of the person actually receiving, but it might scare off people who haven’t been instructed in proper reception).
I know as first communicants were were able to practice reception both in the hands (making the throne) and on the tongue. As well as practice reception of the wine. I don’t know about RCIA, but they really should have everyone practice both, based on some of the fear expressed here. (BTW if you have normal saliva production, the host should stick to your tongue and it won’t fall off).