While there are always going to be "eye of the beholder" type issues regarding personal preferences in traveller reports, from what I've seen, NH Altona is very underrated on this sight. Maybe I just got lucky, but my "smoking room" had a balcony, and was above average size for a standard Euro room. At less than 100 euro per night, is was a comparative bargain.
Hamburg is probably the funkiest of major German cities, a plus in my opinion, and there are many interesting sights around town besides the uppercrust midtown area. NH Altona is within a 20 minute walk of the much hyped Reeperbahn ("Sinful Mile") area (not really as sleezy as many reports indicate, more like a big party street), and there are many interesting restaurants/cafes (many Italian) along the way. The harbor area is also relatively close, but a tricky walk due to street/bridge layout.
A big tourist tip is to check out the Sunday, pre-dawn concerts at the fishmarket area, live bands rocking at 5 am (to approx 10am) most weekends. Hamburg bus service is great, and there is a stop very close to hotel. NH Altona is good location for O2 Arena, I was working at O2 that weekend and caught a bus at 3am after only 10 minute wait, admittedly lucky schedule wise. Be advised that the bus stop is at least 10 minute walk from arena, and it often rains.
Hamburg is said to have the most per-capita rich folks in Deutschland, but it also appeared to have all the street people, hippies, and freaks, also a plus for me since Hamburg prices here seem to be the most affordable I've seen in Germany. As John Lennon reportedly said, "I was born in Liverpool but I grew up in Hamburg".
True, Altona is approximately 25 minutes to the "centrum" by bus, but if I could find walking shortcuts in just a couple days, I'm sure there are others. Anyone who couldn't find decent eateries, pubs, etc, in vicinity must not have looked farther than the lobby door, and that includes the McDonalds arches two blocks away. Altona is currently considered trendy/fashionable in travel blog land.
Directly across the street from NH is a place called "Graceland" which has by some of the best southern style USA bar-b-que I've found in western Europe (holds up great against places like Memphis and KC, believe it or not). Around 10 minutes or less walk away is an area where old gasworks buildings have been renovated, there is a fine health/swimming club "Holmes Place" (fees), if Hamburg strolling isn't enough of a workout.
The Altona also has a decent rooftop spa (hardly any equipment), with sparkling new, little used steam and sauna. There is also a nice, small rooftop area where you can see a decent panorama of the city perimeters. I parked free for 2 days, and it seemed like there was enough room for a few dozen autos even before "creative positioning" came into play. If not, safe streets right next door.
Free internet in lobby was spotty and 10 euro charge for wifi in room a minus.The lobby, spa and conference areas seemed remodeled, rooms/floor I was on did not.
If you need to be in the center of Hamburg look elsewhere, but for overall value, service and convenience NH Altona was a good deal for me.