I was there just pre-Covid. Pair Xi-an together with Luoyang. Go around Mid April in time for the Peony season. You can visit a lot of parks - both paid and free - with the Peonies in full bloom. FYI, peony is the national flower of China. Luoyang - you can visit the Longmen Grottoes - very impressive. You can travel to Luoyang easily by high speed train from Xi-an. I find Xi-an very interesting - Bell Tower, Drum Tower, Muslim food etc besides the terracotta . You can also try their shopping malls. Quite interesting. There is also a night street which I forgotten the name which is very interesting. You don't have to do Huashan if you have eldery folks.