A kneeler helps. I’m nearly 60 and suffering from a bad bout of sciatica. Kneeling is painful for me, and kneeling on the floor especially so. I can still manage it on a kneeler though. So if you don’t use a kneeler, expect fewer people kneeling, and you’ll lose consistency in liturgy. For someone interested in good liturgy, unity in liturgical acts adds an important dimension.
As for receiving on the tongue or in the hand… I receive in the hand, but at the abbey where I go to Mass, many do receive on the tongue, and on their knees. Many older monasteries did not have altar rails either. They opened the grille of the enclosure and one or two of the priest-monks came out to distribute communion to the faithful lined up two-by-two.