Campy works well stock, but when it comes to mix and match Shimano is king. I slapped a brand new 7 speed freewheel on my 1987 Shimano 105 hub and shift it with Sora ST3300 brifters. Can you do the same with Campy? Nope . You’d be lucky to even find a freewheel for an Italian threaded hub. And Campy never made a 7 sp brifters, so you are out of luck if you want to stay 126mm. On another bike I was able to convert a 130mm RSX hub to 126mm by just taking out one spacer. I don’t see how you can shorten a newish Campy hub. You can also run 8 of 9 on 7 with Shimano hubs. With Campy the 8 speed hubs are in a lost universe in its own and there is no good choice for staying with 126mm hub width while using brifters.
similarly for the front. Campy cranks shorter than 170mm are rarer than hens teeth whereas 165mm Shimano cranks are at least out there. The most recent 105 goes down to 160mm. And you have at least tons of aftermarket alternatives with Shimano’s 110mm and 130mm bolt patterns. With campy your obscure 135? Mm bolt pattern means no luck finding replacement rings and that ISO sq taper BB spindle means no interchangeability with other brands neither.