If you mean open-world PvE, anything works fine and it’s definitely possible to be a good DPS dealer with GS and Axe/Axe. Go full zerk with Strength runes + Sigil of Force, Accuracy, Air, Fire, etc. (maybe do some maths to optimize your damage).
Just be a little careful in HoT and LS3 maps where mobs hit hard and you need to be a little less lazy.
Also consider having a ranged swap, namely Longbow: it’s very useful for disengaging when things get tough and the AoE skills will help you deal with packs of mobs (actually, always start ranged and then melee with GS or Axe/Axe).
On the other hand, instanced content (Dungeons, Fractals, Raids, in order of difficulty) will require a much more focused build (same gear, though). Go with classic Phalanx Strength with EA and Banners, or check Fractals/Raids sections on Metabattle for other options.