I bought Activa 125 last year - One thing I missed is the headlight, it is bad, way too dim to be able to see potholes even in a city. My father's 2010 Activa's headlight is more useful.
Whatever you buy, do a test ride at night & check the headlight.
I decided against NTorq because of mileage concerns. I wanted to try Jupiter 125 but showroom people were not interested in showing me that, instead were pushing Ntorq. Access 125 is considered good, I don't remember why I decided against that. Did not pick Dio 125 because it didn't support those guards over the body towards the front.
Activa is known to just work w/o much concern. The major problem with my father's Activa was cold starting. This is resolved in new models. I get ~50kmpl mileage in Bengaluru, which will drop to 45kmpl if traffic is bad, but have seen an average of 55kmpl when roads are relatively empty (saw this in Dec last week & Jan first week - my commute is just under 40km per day). Unhappy with my local service centre, will change it for next service (kind of a plus point that there are many service centres).