Kind of hard to beat the 15 plus 1 on the 43x.
Very little difference in a 43 and 43x. The 43x is .7 oz heavier but has better grip and capacity. Yes the grip is a little longer but to me it is worth it.
If I want something smaller I just carry the G42.
Or just go with the G18 "spray and pray" model @bernardo G43X has a better feel to my hand but I would base more along $ and feel to you and how you plan to carry. Glock stepped up their game a bit with barrels on both of these CC models.
Most experienced shooters (myself included) find the G48 to shoot a wee bit flatter (i.e. less muzzle rise) due to the longer slide. Since the butt of the gun is the challenging part to conceal, there's no real downside to using the longer G48 for concealed carry.
If you already have a G43, the G43X will fit the same holster, but I personally wouldn't find that to be compelling reason to choose one over the other.