That can be done better by encouraging another tradition, of people celebrating these occasions amongst themselves, as secular, national festivals, visiting monuments, museums, mausoleums to pay homage to great men who built their republic as well as the soldiers who laid down their lives preserving it. India Gate, our most important war memorial, itself could be a venue for a more solemn, informal ceremony to pay homage to the Unknown Soldier. In the US, people even visit the Vietnam War memorial in thousands. Here, muck lies all around even Gandhi Samadhi unless someone spruces it up for a foreign dignitary's visit. A mature republic does not need the reassurance of a trailer-mounted Prithvi on its Republic Day.
Military parades are great, they are also inspirational.
But leave them to the armies and suitable military occasions. Yes, the president and the prime minister should deliver their message to the nation on these days. But why not leave the celebrations to the people who'd be happier displaying the flag on their rooftops rather than watching the big shots do it on television, while their cities are under siege because of terrorist threats and VIP movements.