You can definitely find a "jack-of-all-trades" bike that will DH amazing, and also pedal/climb well.
If I was in your shoes, I'd be looking at a Santa Cruz Bronson or Nomad (both 27.5) or a Hightower LT (29er). All 3 of these will do it all, the Nomad will have the edge on DH, the other two will edge out on climbing. All are amazing though, just depends on what you want to emphasize most and if you want to stay 29er or go 27.5.
Take a look at these and let me know which one you think is a best fit for you and I will give some other options/brands/models.
Nomad V4 MY18
Bronson V2 MY18
Hightower LT V1 MY18
Another good option is a Trek Remedy, it is a very capable bike. I have a buddy who races enduro on one, so I know it can do DH and climb well.
Remedy 9.9 Race Shop Limited | Trek Bikes
For what you're looking for I'd think about going somewhere around 150-170mm travel for the shocks (my guess is that your Giant is 120mm in the back).
Let me know what you think of any of these and I'll spit out some more options.