Is my dragonite good? v2.0

Not good. If the level is good, like cp>2000+ you can use it to attack.

Dragon Breath and Hyper Beam is a good offensive moveset.

Dragon Breath is also Legacy.

If it's already at 2000+ CP, you can definitely use it as an attacker. You may consider powering it up if you REALLY want to have an attacker with that moveset (and have ample stardust to use), whether Dratini candies are rare (so you won't evolve another one) or plentiful (so it doesn't take much effort to power) it can be justifiable. Although most players here are IV-addicts that will tell you anything under 90% is poor (I only have a handful of pokemon that are 90% or higher... I'm very happy with anything over 80% and often pleased with 70%+ if it has good moves).

I have a 1.1.12 31% DB/DC that i caught at level 26ish. I powered it up to level 30 and it has a CP of 2751 now. Its my dedicated attacking mon, I never drop it off in gyms. I drop all my high IV level 30+ Dnites including other DB Dnites I have. I find that my 96% 3200CP DBDC does the similar damage as the level 30 31% iv one. If I had 2-3 more low IV ones with DB id use them all for fighting gyms.
If yours is a suitable level Id definitely power it up.