Having flown both AC J and LH J many times, my comments are:

seat / hard product: AC wins hands down due to privacy and direct aisle access for all pax (unless you want to hold your SO's hands during the flight or enjoy climbing over a stranger)

wifi: as mentioned above, AC does not have wifi on TATL routes

service: I would rate AC slightly higher, but it somewhat boils down to personal preferences: AC may be slightly more casual and service can take a while while LH FAs tend to be somewhat more formal/impersonal and efficient (FWIW, I'm fluent in English and German and can appreciate both styles)

food: AC's menu is slightly more extensive (more courses and more choices), though quality of the food is at least as good on LH

drinks: IMO LH offers better wines and champagne

Everything else being somewhat similar, I'd always choose AC due to the much superior hard product.